First Council of Nicaea

{{Short description|Council of Christian bishops in Nicaea, 325}}
{{Too many sections|date=January 2024}}
{{Use dmy dates|date=May 2018}}
{{Infobox Ecumenical council
| image =Nikea-arius.png 
| caption =The Council of Nicaea, with Arius depicted as defeated by the council, lying under the feet of Emperor Constantine. 
| council_name = First Council of Nicaea
| council_date = May to August AD 325
| accepted_by =
* [[Catholic Church]]
* [[Eastern Orthodox Church]]
* [[Oriental Orthodox Church]]
* [[Church of the East]]
| next = [[First Council of Constantinople]]
| convoked_by = [[Constantine the Great|Emperor Constantine I]]
| presided_by = [[Hosius of Corduba]] and [[Pope Alexander I of Alexandria]]
| attendance = {{ubl|318 (traditional number)|250–318 (estimates) – only five from Western Church}}
| topics = [[Arianism]], the nature of Christ, celebration of Passover, [[ordination]] of eunuchs, prohibition of kneeling on Sundays and from Easter to Pentecost, validity of [[baptism]] by heretics, lapsed Christians, sundry other matters.<ref name="harvnb|SEC|pp=112–114">{{harvnb|SEC|pp=112–114}}</ref>
| documents = [[Nicene Creed#Original Nicene Creed of 325|Original Nicene Creed]],<ref name="harvnb|SEC|p=39">{{harvnb|SEC|p=39}}</ref> 20 [[Canon (canon law)|canons]],<ref name="harvnb|SEC|pp=44–94">{{harvnb|SEC|pp=44–94}}</ref> and a synodal epistle<ref name="harvnb|SEC|pp=112–114" />
}}
{{Eastern Orthodox sidebar|expanded=councils}}
{{Oriental Orthodox sidebar}}
{{Ecumenical councils of the Catholic Church}}

The '''First Council of Nicaea''' ({{IPAc-en|n|aɪ|ˈ|s|i:|ə}} {{respell|ny|SEE|ə}}; {{lang-grc|Σύνοδος τῆς Νικαίας|Sýnodos tês Nikaías}}) was a council of Christian bishops convened in the [[Bithynia]]n city of [[Nicaea]] (now [[İznik]], [[Turkiye]]) by the [[Roman emperor|Roman Emperor]] [[Constantine the Great|Constantine I]]. The Council of Nicaea met from May until the end of July 325.<ref>{{Cite book |last=Hanson |first=R.P.C. (Richard Patrick Crosland ) |title=The Search for the Christian Doctrine of God: The Arian Controversy, 318-381 |date=1988 |year=1988 |isbn=978-0-567-09485-8 |pages=152|publisher=T. & T. Clark }}</ref> 

This [[ecumenical council]] was the first of many efforts to attain [[consensus decision-making|consensus]] in the church through an [[legislature|assembly]] representing all [[Christendom]]. [[Hosius of Corduba]] may have presided over its deliberations.<ref name="Carroll 1987 11">{{harvnb|Carroll|1987|p=11}}</ref>{{sfn|Vallaud|1995|pp=234–235, 678}} Its main accomplishments were settlement of the [[Christology|Christological]] issue of the divine nature of [[God the Son]] and his relationship to [[God the Father#Christianity|God the Father]],<ref name="harvnb|SEC|p=39" /> the construction of the first part of the [[Nicene Creed]], mandating uniform observance of the [[date of Easter]],<ref name="ReferenceB">{{harvnb|On the Keeping of Easter}}</ref> and promulgation of early [[canon law]].<ref name="harvnb|SEC|pp=44–94" /><ref>{{harvnb|Leclercq|1911b}}</ref>

== Ecumenical Council ==
The First Council of Nicaea was the first [[ecumenical council]] of the church. Nicaea "was the first time that any attempt had been made to summon a general council of the whole church at which, at least in theory, the church in every part of the Roman Empire should be represented".<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 152</ref> 

Derived from [[Koine Greek|Greek]] ({{lang-grc|οἰκουμένη|oikouménē|the inhabited one}}), "ecumenical" means "worldwide" but generally is assumed to be limited to the known inhabited Earth,<ref>{{citation |last=Danker |first=Frederick William |title=A Greek-English Lexicon of the New Testament and Other Early Christian Literature |url=https://books.google.com/books?id=hd7bZxvlbFsC |year=2000 |access-date=2014-02-24 |chapter=οἰκουμένη |edition=Third |location=Chicago |publisher=University of Chicago Press |isbn=978-0-226-03933-6 |author-link=Frederick William Danker}}</ref> and at this time in history is nearly synonymous with the [[Roman Empire]]. The earliest extant uses of the term for a council are [[Eusebius]]' ''Life of Constantine''<ref>{{harvnb|Vita Constantini|loc=Book 3, Chapter 6}}</ref> around 338, which states "he convoked an ecumenical council" ({{lang|grc|σύνοδον οἰκουμενικὴν συνεκρότει}}, {{transl|grc|sýnodon oikoumenikḕn synekrótei}})<ref name="ReferenceA">{{harvnb|Ad Afros Epistola Synodica}}</ref> and a letter in 382 to [[Pope Damasus I]] and the Latin bishops from the [[First Council of Constantinople]].<ref>{{harvnb|SEC|pp=292–294}}</ref>

Historically significant as the first effort to attain [[consensus decision-making|consensus]] in the church through an [[legislature|assembly]] representing all of [[Christendom]],<ref name="Kieckhefer 1989">{{harvnb|Kieckhefer|1989}}</ref> the Council was the first occasion where the technical aspects of [[Christology]] were discussed.<ref name="Kieckhefer 1989" /> Through it a precedent was set for subsequent general councils to adopt [[creed]]s and [[Canon (canon law)|canons]]. This Council is generally considered the beginning of the period of the [[first seven ecumenical councils]] in the [[history of Christianity]].<ref>{{cite web |title=The First Seven Ecumenical Councils – MOLL-Y – The Method of Loci Learning – York |url=http://moll-y.co.uk/first-seven-ecumenical-councils/ |access-date=July 10, 2020}}</ref>

== Attendance ==
Constantine had invited all 1,800 bishops of the Christian church within the Roman Empire (about 1,000 in the East and 800 in the [[Western Roman Empire|West]]), but a smaller and unknown number attended. [[Eusebius]] of Caesarea counted more than 250,<ref>{{harvnb|''Vita Constantini''|loc=iii.7}}</ref> [[Athanasius of Alexandria]] counted 318,<ref name="ReferenceA" /> and [[Eustathius of Antioch]] estimated "about 270"<ref>{{harvnb|Theodoret|loc=Book 1, Chapter 7}}</ref> (all three were present at the Council). Later, [[Socrates of Constantinople|Socrates Scholasticus]] recorded more than 300,<ref>{{harvnb|Theodoret|loc=Book 1, Chapter 8}}</ref> and [[Evagrius Scholasticus|Evagrius]],<ref>{{harvnb|Theodoret|loc=Book 3, Chapter 31}}</ref> [[Hilary of Poitiers]],<ref>{{harvnb|''Contra Constantium Augustum Liber''}}</ref> [[Jerome]],<ref>{{harvnb|''Temporum Liber''}}</ref> [[Dionysius Exiguus]],<ref>{{harvnb|Teres|1984|p=177}}</ref> and [[Tyrannius Rufinus|Rufinus]]<ref name="Kelhoffer 2011">{{harvnb|Kelhoffer|2011}}</ref> each recorded 318. This number 318 is preserved in the liturgies of the [[Eastern Orthodox Church]]<ref>{{harvnb|''Pentecostarion''}}</ref> and the [[Coptic Orthodox Church]].<ref>{{Cite web |title=3. St. Basil Anaphora أنافورا القديس باسيليوس :: The Commemoration of the Saints :: مجمع القديسين |url=https://tasbeha.org/hymn_library/view/2045#:~:text=the%20three%20hundred%20and%20eighteen%20assembled%20at%20Nicea |access-date=2022-10-12 |website=tasbeha.org}}</ref> For some, the number is suspicious as it is the number of [[Abraham]]'s servants in Genesis 14:14, and there was a polemical reason for the Nicene Fathers to imply that they were servants of Abraham, the father of the Faith.<ref>{{citation |last=Смелова |first=Н.С. |title=Правила Первого Вселенского Никейского собора по рукописи Сир. 34 из собрания ИВР РАН |url=http://www.orientalstudies.ru/rus/images/pdf/PPV_2009_2-2_smelova.pdf |year=2009 |access-date=2022-07-20 |archive-url=https://web.archive.org/web/20220223045143/http://www.orientalstudies.ru/rus/images/pdf/PPV_2009_2-2_smelova.pdf |archive-date=2022-02-23}}</ref> Considering this, Hanson concludes, "The number of bishops at the Council of Nicaea probably fell between 250 and 300." (RH, 156)

The bishops did not come alone; each one had permission to bring with him two priests and three [[deacon]]s, so the total number in attendance could have been above 1,800. Eusebius speaks of an almost innumerable host of accompanying priests, deacons, and [[acolyte]]s. A Syriac manuscript lists the names of the eastern bishops which included 22 from [[Coele-Syria]], 19 from [[Syria Palaestina]], 10 from [[Phoenicia]], 6 from [[Arabian Peninsula|Arabia]], others from [[Assyria]], [[Mesopotamia]], [[Iran|Persia]], etc., but the distinction of bishops from presbyters had not yet formed.<ref>Hitti, Philip K. (1951) History of Syria including Lebanon and Palestine. New York: The Macmillan Company. p. 363 fn.</ref><ref>Cowper, B. H. (1861). Syriac Miscellanies. London:Williams and Norgate. pp. 9–10. [https://www.preteristarchive.com/Books/1861_syriac-miscellanies.html Preterist Archive website] {{Webarchive|url=https://web.archive.org/web/20181007165807/http://www.preteristarchive.com/Books/1861_syriac-miscellanies.html|date=7 October 2018}} Retrieved 2 April 2018.</ref>

Delegates came from every region of the Roman Empire and from the Christian churches extant within the [[Sasanian Empire|Sassanid Empire]].<ref>{{cite web |year=2007 |title=''Ancient See of York'' |url=http://www.newadvent.org/cathen/15733b.htm |access-date=25 October 2007 |publisher=New Advent}}</ref> However, "the Council was overwhelmingly Eastern, and only represented the Western Church in a meagre way." (RH, 156) Referring to an event in 335, Ayres says that “the Western bishops … had hitherto remained on the periphery of the controversy." (LA, 272) "Hilary, for instance, never really understood the Arian Controversy till he reached the East as a result of being exiled." (RH, 170) 

Many of the assembled fathers—for instance, [[Paphnutius of Thebes]], [[Potamon of Heraclea]], and [[Paul of Neocaesarea]]—had stood forth as [[confessor]]s of the faith and came to the Council with the marks of persecution on their faces. This position is supported by patristic scholar [[Timothy Barnes (classicist)|Timothy Barnes]] in his book ''Constantine and Eusebius''.<ref>{{harvnb|Barnes|1981|pp=214–215}}</ref> Historically, the influence of these marred confessors has been seen as substantial, but recent scholarship has called this into question.<ref name="Kelhoffer 2011" /> 

Of the Eastern bishops, the first rank was held by the [[patriarch]]s: [[Pope Alexander I of Alexandria|Alexander of Alexandria]] and [[Eustathius of Antioch]]. "Marcellus, Eustathius and Alexander were able to make common cause against the Eusebians." (LA, 69) "If we are to take the creed N at its face value, the theology of Eustathius and Marcellus was the theology which triumphed at Nicaea. That creed admits the possibility of only ''one ousia and one hypostasis''. This was the hallmark of the theology of these two men." (RH, 235) 

Other notable participants were [[Eusebius of Nicomedia]] and [[Eusebius|Eusebius of Caesarea]], the purported first church historian. Circumstances suggest that [[Saint Nicholas|Nicholas of Myra]] attended (his life was the seed of the [[Santa Claus]] legends); [[Macarius of Jerusalem]], later a staunch defender of Athanasius; [[St. Aristaces I|Aristaces of Armenia]] (son of Saint [[Gregory the Illuminator]]); [[Leontius of Caesarea]]; [[Jacob of Nisibis]], a former [[hermit]]; [[Hypatius of Gangra]]; Protogenes of Sardica; Melitius of Sebastopolis; [[Achillius of Larissa|Achilleus of Larissa]] (considered the Athanasius of [[Thessaly]]);{{sfn|Atiya|1991}} and [[Saint Spyridon|Spyridon of Trimythous]], who even while a bishop made his living as a [[shepherd]].<ref>{{harvnb|Vailhé|1912|p=}}</ref> From foreign places came John, bishop of Persia and [[Saint Thomas Christians|India]],<ref>{{Cite web |last=Valley |first=Marthoma Church of Silicon |title=History of Marthoma Church – Marthoma Church of Silicon Valley |url=http://mtcsv.org/history-of-marthoma-church/ |access-date=2020-09-03 |language=en-US}}</ref> [[Theophilus (bishop of the Goths)|Theophilus]], a [[Goths|Gothic]] bishop, and Stratophilus, bishop of [[Pitsunda|Pitiunt]] in Georgia. The [[Latin]]-speaking provinces sent at least five representatives: [[Marcus of Calabria]] from [[Roman Italy|Italia]], [[Caecilianus|Cecilian of Carthage]] from [[Africa (Roman province)|Africa]], [[Hosius of Corduba|Hosius of Córdoba]] from [[Hispania]], [[Nicasius of Die]] from [[Gaul]],{{sfn|Atiya|1991}} and [[Domnus of Pannonia|Domnus of Sirmium]] from the province of the [[Danube]]. . [[Alexander of Constantinople]], then a presbyter, was also present as representative of his aged bishop.{{sfn|Atiya|1991}} 

"Athanasius was certainly present as a deacon accompanying Alexander of Alexandria. … But it is equally certain that he can have taken no prominent nor active part, in spite of later legends to this effect and the conviction of some scholars that he was the moving spirit in the Council." (RH, 157) Athanasius eventually spent most of his life battling against Arianism

The supporters of Arius included [[Secundus of Ptolemais]], Theonus of Marmarica, Zephyrius (or Zopyrus), and Dathes, all of whom hailed from the [[Cyrenaica#Christianization|Libyan Pentapolis]]. Other supporters included [[Eusebius of Nicomedia]], [[Paulinus of Tyrus]], Actius of Lydda, Menophantus of Ephesus, and [[Theognis of Nicaea|Theognus of Nicaea]].{{sfn|Atiya|1991}}<ref>{{harvnb|Photius I|loc=Book 1, Chapter 9}}</ref>

== Arian Controversy ==
The main purpose of the Council was to resolve disagreements brought about by the [[Arian controversy]] in the [[Greek East and Latin West|Greek-speaking east]].<ref>{{harvnb|Carroll|1987|p=10}}</ref> A dispute arose from within the [[Church of Alexandria]] over the nature of [[Jesus]] in his relationship to the Father: in particular, whether the Son had been 'begotten' by the Father from his own being, and therefore having no beginning, or else created out of nothing, and therefore having a beginning.<ref name="kelly1978">{{harvnb|Kelly|1978|loc=Chapter 9}}</ref> [[Pope Alexander I of Alexandria|St. Alexander of Alexandria]] and [[Athanasius of Alexandria|Athanasius]] took the first position; the popular [[presbyter]] [[Arius]], from whom the term [[Arianism]] comes, took the second. To most bishops, the teachings of Arius were [[Heresy in Christianity|heretical]] and dangerous to the [[Salvation in Christianity|salvation]] of souls.<ref>{{harvnb|Ware|1991|p=28}}</ref> 

The Council decided against the Arians overwhelmingly (of the estimated 250–300 bishops present, all but two agreed to sign the creed, and these two, along with Arius, were banished to [[Illyria]]).<ref name="EB1911" /><ref>{{harvnb|Schaff|Schaff|1910|loc=Section 120}}</ref>

=== The Nicene Creed ===
Most significantly, this council formulated the [[Nicene Creed]]. With the creation of the creed, a precedent was established for subsequent local and regional councils of bishops ([[synod]]s) to create statements of belief and [[Canon (canon law)|canons]] of doctrinal [[orthodoxy]]—the intent being to define unity of beliefs for the whole of [[Christendom]].<ref name="EB1911">{{cite EB1911 |wstitle=Nicaea, Council of |volume=19 |pages=640–642 |first=Carl Theodor |last=Mirbt}}</ref>

=== Easter ===
Another result of the Council was an agreement on when to celebrate Easter, the most important feast of the ecclesiastical calendar, decreed in an [[epistle]] to the Church of Alexandria in which is simply stated:<blockquote>We also send you the good news of the settlement concerning the holy pasch, namely that in answer to your prayers this question also has been resolved. All the brethren in the East who have hitherto followed the Jewish practice will henceforth observe the custom of the Romans and of yourselves and of all of us who from ancient times have kept Easter together with you.<ref>{{harvnb|SEC|p=114}}</ref></blockquote>

== Constantine's role ==

=== Before Nicaea ===
In the first place, Constantine legalized Christianity. During the first three centuries, the Roman authorities persecuted Christianity. The [[Diocletianic Persecution]] of 303-313 was the most severe persecution of Christians up to that point in history. Diocletian's first edict commanded churches and holy sites razed to the ground, sacred articles burned, and believers jailed. However, in 313, the Western Roman Emperor Constantine (306–337) legalized Christianity through the Edict of Milan. He granted Christians "the right of open and free observance of their worship."

“In 324 the Emperor Constantine … (who recently) assumed control of the whole empire, took an interest in the dispute. Constantine wrote to Alexander and Arius telling them to stop quarrelling about what seemed to him to be such a small matter.”<ref>Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 17-18</ref> Constantine wrote:<blockquote>“For as long as you continue to contend about these small and very insignificant questions, I believe it indeed to be not merely unbecoming, but positively evil, that so large a portion of God’s people which belong to your jurisdiction should be thus divided.”<ref>Davis, Leo Donald. The First Seven Ecumenical Councils (325-787): Their History and Theology. Vol. 21. Collegeville, Minn: Liturgical Press, 1990. 55</ref></blockquote>Constantine, therefore, attempted to intervene even before he understood what this dispute was about. “It initially took the efforts of bishops like Ossius and Alexander of Alexandria to persuade him that anything significant was at issue in Alexandria.”<ref>Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 87-88</ref>

A few months before the Council of Nicaea, “early in 325,” an “anti-Arian Council”<ref>Hanson RPC, page 131</ref> was held in Antioch,<ref>Hanson RPC, page 149</ref> consisting mainly of those who sympathized with Alexander.<ref>Hanson RPC, page 130</ref> “In normal circumstances the Metropolitan of the area in which the Council met would have presided … But Constantine's representative, Ossius, took precedence … over Eustathius.”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 155</ref> Ossius was “the Emperor's representative”<ref>Hanson, 154</ref> and Constantine’s “agent.”<ref>Hanson, 190</ref> He was “Constantine's chief adviser and agent in matters concerning the Christian church.”<ref>Hanson, 130</ref> This implies that the meeting took place with the approval of the emperor, which means that, even before Nicaea, "Constantine had taken Alexander's part"<ref name=":1"/> in his dispute with Arius.

=== Calling the council ===
Constantine’s letter failed to unite the warring factions. Consequently. In the year 325, “Constantine himself summoned the bishops”<ref>Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 18</ref> to end this dispute. The council was not called by a church official and nobody asked Constantine to call this meeting. It was his initiative. “It was then certainly Constantine who convoked the Council of Nicaea.”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 153-4</ref> “Religious partisanship has in the past led some scholars to suggest that Silvester, bishop of Rome, convoked the Council of Nicaea, but modern Roman Catholic scholars honourably dismiss this idea.”<ref name=":0"/>

As stated above, Nicaea was the first 'general' or 'ecumenical' council of the church. It was the Roman Emperor Constantine who introduced this concept to the church:<blockquote>“The procedures of a council modelled on methods of Roman governance would have been familiar to Constantine, and we can assume that he saw it as the natural means to achieve consensus within the Church.”<ref>Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 87</ref></blockquote>Furthermore, without the assistance of the emperor, the church was unable to call a general council. Only the emperor could call a general council. “Even Damasus [a later bishop of Rome] would have admitted that he could not call a general council on his own authority.”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 855</ref> “Everybody recognised the right of an Emperor to call a council, or even to veto or quash its being called.”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 849-50</ref>

As his letter to Arius and Alexander shows, Constantine did not call the Nicene Council because he was concerned about right doctrine. “Constantine himself of course neither knew nor cared anything about the matter in dispute.”<ref>McGiffert A.C. A History of Christian Thought, 1954, Vol. 1, p. 258</ref> Rather, “the Council of Nicea was first and foremost an attempt by the Roman emperor Constantine the Great to keep his empire from splitting.”<ref>Pavao, Paul. Decoding Nicea (p. 3). Kindle Edition.</ref> “Constantine himself had become sole emperor only in 324 (after having ruled the western half since 310–12), and he seems to have promoted Christianity as a unifying religion '''for the empire'''.”<ref>Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 87</ref> “Constantine's attitude reflects deeply embedded Roman attitudes about the social function of religion.”<ref>Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 88</ref>

Constantine summoned the bishops of all provinces to [[Nicaea]], a place reasonably [[History of early Christianity|accessible to many delegates]].

Constantine gave the participating bishops free travel to and from their [[episcopal see]]s to the Council, as well as lodging.

=== Presiding officer ===
“The evidence weighs strongly in favour of the view that Ossius … presided at Nicaea.”<ref name=":0">Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 154</ref> “In normal circumstances the Metropolitan of the area in which the Council met would have presided, and in this case it would have been Eusebius of Nicomedia.”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 155</ref> Ossius was “Constantine's chief adviser and agent in matters concerning the Christian church.”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 130</ref> Ossius presided “as the Emperor's representative”<ref name=":0" /> and as Constantine’s “agent.”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 190</ref> “Ossius … represented the policy of Constantine”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 170</ref>

=== Constantine's entrance ===
"Resplendent in purple and gold, Constantine made a ceremonial entrance at the opening of the Council, probably in early June, but respectfully seated the bishops ahead of himself."<ref name="Carroll 1987 11" /> As Eusebius describes, Constantine "himself proceeded through the midst of the assembly, like some heavenly messenger of God, clothed in raiment which glittered as it were with rays of light, reflecting the glowing radiance of a purple robe, and adorned with the brilliant splendor of gold and precious stones."<ref>{{harvnb|''Vita Constantini''|loc=Book 3, Chapter 10}}</ref>

=== Condemnation of Arianism ===
“It became evident very early on that the condemnation of Arius was practically inevitable” (RW, 68). The Nicene Creed “was constructed as a deliberately anti-Arian document.” (RH, 164) “All the more obnoxious doctrines of Arius and his followers are struck at in N in the most impressive way.” (RH, 165)

In spite of [https://revelationbyjesuschrist.com/arius-why-important/#supp the support that Arius enjoyed], only Arius and two of his friends refused to sign, for which they were excommunicated."<ref>Bernard Lohse, A Short History of Christian Doctrine, 1966, p51-53</ref> “In older narratives of the fourth century it was reasonably easy to understand why the Nicene creed was agreed with little dissent: only the few ‘heretics’ would refuse such a clear acknowledgement of the Church's constant faith. Without this older narrative, matters are more complex.”<ref>Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 88</ref>

At the Council of Antioch a few months before Nicaea, the leader of the Eusebians (Eusebius of Caesarea) was provisionally excommunicated. The 'Eusebians' are the larger group that opposed the theology of Alexander and that include Arius and his direct supporters. See - [https://revelationbyjesuschrist.com/lewis-ayres-nicaea-and-its-legacy/#p2.3 The Eusebians] The anti-Arian nature of the Council at Antioch and the excommunication of Eusebius show that, already before Nicaea, "Constantine had taken Alexander's part.”<ref name=":1">Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 89</ref> At Nicaea, “this imperial pressure coupled with the role of his advisers in broadly supporting the agenda of Alexander must have been a powerful force.”<ref name=":1" />

=== Homoousios ===
At the time, the term homoousios (same substance) was the most controversial term in the Nicene Creed. Most delegates at the Council had considerable reservations about the term because, before Nicaea, that term was only preferred by Sabellians, the Bible never says anything about God’s substance (ousia), the term was not part of the standard Christian language at the time, but was “borrowed from the pagan philosophy of the day.” (RH, 846) 

Constantine’s domination of the Nicene Council, therefore, is particularly revealed by the fact that he was able to force the inclusion of the word homoousios. “’Homoousios’ and ‘from the essence of the Father’ were added to the creed by Constantine himself, bearing witness to the extent of his influence at the council.”<ref>Jörg Ulrich. Nicaea and the West. ''Vigiliae Christianae'' 51, no. 1 (1997): 10-24. 15.</ref> Constantine "pressed for its inclusion."<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 211</ref> “Overawed by the emperor, the bishops, with two exceptions only, signed the creed, many of them much against their inclination.”<ref>Britannica, 1971 edition, Vol. 6, “Constantine,” p. 386</ref>

“Constantine took part in the Council of Nicaea and ensured that it reached the kind of conclusion which he thought best.”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 850</ref> The emperor was present as an overseer and presider but did not cast any official vote. Constantine organized the Council along the lines of the [[Roman Senate]].
== Agenda ==
The agenda of the synod included the following issues:
# With respect to the [[Arianism|Arian]] question, the large portion of the [[Nicene Creed]] that is devoted to Christ (more than 80%) indicates that the main issue before the Council was about Jesus Christ; not about the Father or about the Holy Spirit. What the main issue was more exactly can be seen by comparing the condemnations at the end of the decree—reflecting Arius' views—with the council's affirmations as contained in the body of the creed:
##While Arius claimed that Jesus Christ was created, the Council concluded, since He was begotten, that He was not made.
##While Arius argued that Jesus Christ was created out of nothing or out of something else, the council affirmed that he was begotten out of the substance (essence) of the Father.
##Since the statement in the creed that Jesus Christ is [[homoousion]] with the Father (of the same substance)<ref>{{Citation|title=Homoousion|url=https://www.thefreedictionary.com/Homoousion|work=The Free Dictionary|access-date=2021-09-29}}</ref><ref>{{Cite web|title=Henry George Liddell, Robert Scott, A Greek-English Lexicon, ὁμο-ούσιος|url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.04.0057:entry=o(moou/sios|access-date=2021-09-29|website=www.perseus.tufts.edu}}</ref> does not counter any of Arius' claims, as reflected in the condemnation. The debate was not about what his substance is but out of what substance he was generated. The term ''homo-ousios'' was added only because Emperor Constantine proposed and insisted on its inclusion.<ref>{{cite book|last=Norwich |first= John Julius |title=Byzantium: The Early Centuries |publisher= Guild Publishing |location=London |year= 1988|page=55}}</ref><ref>{{Cite web|title=Trinity: The role of Constantine in the Nicene creed|url=https://www.bible.ca/trinity/trinity-history-constantine.htm#:~:text=Constantine%20was%20introduced%20to%20the%20trinity%20debates%20which,they%20viewed%20Jesus%20as%20a%20creature,%20not%20God.|access-date=2021-09-29|website=www.bible.ca}}</ref><ref>Jörg Ulrich. "Nicaea and the West" Vigiliae Christianae 51, no. 1 (1997) p. 15</ref> Both Fortman and Erickson mention that the main issue before the council was "not the unity of the Godhead" but the Son's "full divinity".<ref>Millard J. Erickson, ''God in Three Persons'', pp. 82–85</ref><ref>Edmund J. Fortman, ''The Triune God'', pp. 66–70</ref>
# The date of celebration of Pascha/Easter
# The [[Melitians|Meletian]] schism
# Various matters of church discipline, which resulted in twenty [[Canon (canon law)|canons]]
## Organizational structure of the Church: focused on the ordering of the episcopacy
## Dignity standards for the clergy: issues of ordination at all levels and of suitability of behavior and background for clergy
## Reconciliation of the lapsed: establishing norms for public repentance and penance
## Readmission to the Church of [[Heresy in Christianity|heretics]] and schismatics: including issues of when reordination and/or rebaptism were to be required
## [[Liturgy|Liturgical]] practice: including the place of deacons and the practice of standing at prayer during liturgy<ref>{{harvnb|Davis|1983|pp=63–67}}</ref>

== Procedure ==
The Council was formally opened 20 May 325, in the central structure of the imperial palace at Nicaea, with preliminary discussions of the Arian question. Emperor Constantine arrived nearly a month later on 14 June.<ref name="The First Council of Nicaea">{{cite web|url=http://www.newadvent.org/cathen/11044a.htm|publisher=New Advent|title=''The First Council of Nicaea''|access-date=12 October 2017}}</ref> 

=== Arian presentation ===
In these discussions, some dominant figures were Arius, with several adherents. "Some 22 of the bishops at the Council, led by Eusebius of Nicomedia, came as supporters of Arius. But when some of the more shocking passages from his writings were read, they were almost universally seen as blasphemous."<ref name="Carroll 1987 11" /> Bishops Theognis of Nicaea and [[Maris (bishop)|Maris of Chalcedon]] were among the initial supporters of Arius.

=== Eusebius' creed ===
Eusebius of Caesarea called to mind the baptismal creed of his own [[diocese]] at [[Caesarea Maritima|Caesarea]] at Palestine, as a form of reconciliation. The majority of the bishops agreed. For some time, scholars thought that the original Nicene Creed was based on this statement of Eusebius. Today, most scholars think that the creed is derived from the baptismal [[creed of Jerusalem]], as [[Hans Lietzmann]] proposes.<ref>{{Cite book |last=Gollahon |first=Mickey |title=Moses, the ten commandments & the council of nicaea |date=2018 |publisher=lulu.com |isbn=978-0-359-05203-5 |pages=24 |oclc=1057650590}}{{sps|date=April 2022}}</ref>

=== The Nicene Creed ===
The orthodox bishops won approval of every one of their proposals regarding the creed. After being in session for an entire month, the Council promulgated on 19 June the [[Nicene Creed#Original Nicene Creed of 325|original Nicene Creed]]. This profession of faith was adopted by all the bishops "but two from [[Ancient Libya|Libya]] who had been closely associated with Arius from the beginning".<ref name="Carroll 1987 12">{{harvnb|Carroll|1987|p=12}}</ref> No explicit historical record of their dissent actually exists; the signatures of these bishops are simply absent from the creed. The sessions continued to deal with minor matters until 25 August.<ref name="The First Council of Nicaea"/>

== Arian controversy ==
{{Main|Arius|Arianism|Arian controversy}}

=== The two views ===
[[File:Constantine burning Arian books.jpg|thumb|upright|The synod of Nicaea, Constantine and the condemnation and burning of Arian books, illustration from a northern Italian compendium of [[canon law]], {{circa|825}}]]

The [[Arian controversy]] arose in [[Alexandria]] when the newly reinstated presbyter [[Arius]]<ref>{{harvnb|Anatolios|2011|p=44}}</ref> began to spread doctrinal views that were contrary to those of his bishop, [[Pope Alexander I of Alexandria|Alexander of Alexandria]]. The disputed issues centered on the natures and relationship of [[God the Father|God (the Father)]] and the [[Son of God (Christianity)|Son of God (Jesus)]]. The disagreements sprang from different ideas about the [[Godhead in Christianity|Godhead]] and what it meant for Jesus to be God's Son. Alexander maintained that the Son was divine in just the same sense that the Father is, coeternal with the Father, else he could not be a true Son.<ref name="kelly1978" /><ref name="Davis 1983 52–54" />

Arius emphasized the supremacy and uniqueness of God the Father, meaning that the Father alone is almighty and infinite, and that therefore the Father's divinity must be greater than the Son's. Arius taught that the Son had a beginning and that he possessed neither the eternity nor the true divinity of the Father, but was rather made "God" only by the Father's permission and power, and that the Son was rather the first and the most perfect of God's creatures.<ref name="kelly1978" /><ref name="Davis 1983 52–54">{{harvnb|Davis|1983|pp=52–54}}</ref>

[[File:Belgrade grafiti - First Council of Nicaea.jpg|thumb|upright|A grafitti in [[Belgrade]], [[Serbia]], depicting apocryphal events at the First Council of Nicaea. The text reads "St. Nicholas at the council in Nicaea in the year 325 stops the great lie of the heretic Arius who convinced the people that Jesus Christ is not God".]] The Arian discussions and debates at the Council extended from about 20 May through about 19 June.<ref name="Davis 1983 52–54" /> According to legendary accounts, debate became so heated that at one point, Arius was struck in the face by Nicholas of Myra, who would later be [[Canonization|canonized]].<ref>{{harvnb|OCA|2014}}</ref> This account is almost certainly apocryphal, as Arius would not have been present in the council chamber because he was not a bishop.<ref>{{harvnb|González|1984|p=164}}</ref>

Much of the debate hinged on the difference between being "born" or "created" and being "begotten". Arians saw these as essentially the same; followers of Alexander did not. The exact meaning of many of the words used in the debates at Nicaea were still unclear to speakers of other languages. [[Koine Greek|Greek]] words like "essence" ({{transl|grc|[[ousia]]}}), "substance" ({{transl|grc|[[Hypostasis (religion)|hypostasis]]}}), "nature" ({{transl|grc|[[physis]]}}), "person" ({{transl|grc|[[prosopon]]}}) bore a variety of meanings drawn from pre-Christian philosophers, which could not but entail misunderstandings until they were cleared up. The word {{transl|grc|[[Homoousian|homoousia]]}}, in particular, was initially disliked by many bishops because of its associations with [[Gnosticism|Gnostics]] (who used it in their theology), and because their beliefs had been condemned at the 264–268 [[Synods of Antioch]].

=== Arguments for Arianism ===
According to surviving accounts, the presbyter Arius argued for [[Subordinationism|the supremacy of God the Father]], and maintained that the Son of God was created as an act of the Father's will, and therefore that the Son was a creature made by God, begotten directly of the infinite eternal God. Arius's argument was that the Son was God's first production, before all ages, the position being that the Son had a beginning, and that only the Father has no beginning. Arius argued that everything else was created through the Son. Thus, said the Arians, only the Son was directly created and begotten of God; and therefore there was a time that he had no existence. Arius believed that the Son of God was capable of his own [[Free will in theology#Christianity|free will]] of right and wrong, and that "were He in the truest sense a son, He must have come after the Father, therefore the time obviously was when He was not, and hence He was a finite being",<ref>{{harvnb|M'Clintock|Strong|1890|p=45}}</ref> and that he was under God the Father. Therefore, Arius insisted that the Father's divinity was greater than the Son's. The Arians appealed to Scripture, quoting biblical statements such as "the Father is greater than I" ([[John 14|John 14:28]]),<ref>{{bibleref|John|14:28}}</ref> and also that the Son is "firstborn of all creation" ([[Colossians 1:15]]).<ref>{{bibleref|Colossians|1:15}}</ref>

=== Arguments against Arianism ===
The opposing view stemmed from the idea that begetting the Son is itself in the nature of the Father, which is eternal. Thus, the Father was always a Father, and both Father and Son existed always together, eternally, coequally and consubstantially.<ref>{{harvnb|Davis|1983|p=60}}</ref> The anti-Arian argument thus stated that the [[Logos (Christianity)|Logos]] was "eternally begotten", therefore with no beginning. Those in opposition to Arius believed that to follow the Arian view destroyed the unity of the [[Godhead in Christianity|Godhead]] and made the Son unequal to the Father. They insisted that such a view was in contravention of such Scriptures as "I and the Father are one" (John 10:30)<ref>{{bibleref|John|10:30}}</ref> and "the Word was God" (John 1:1).<ref>{{bibleref|John|1:1}}</ref> They declared, as did Athanasius,<ref>On the Incarnation, ch 2, section 9, "... yet He Himself, as the Word, being immortal and the Father's Son"</ref> that the Son had no beginning but had an "eternal derivation" from the Father and therefore was coeternal with him and equal to God in all aspects.{{sfn|Athanasius|Newman|1920|p=[https://books.google.com/books?id=A7ZaAAAAYAAJ&pg=PA51 51]<!--Retrieved 24 May 2014 -->}}

=== Result of the debate ===
[[File:30-manasses-chronicle.jpg|thumb|The first Council of Nicaea from the [[Constantine Manasses|Manasses Chronicle]].]]
The Council declared that the [[God the Son|Son]] was true God, coeternal with the Father and begotten from his same substance, arguing that such a doctrine best codified the Scriptural presentation of the Son as well as traditional Christian belief about him handed down from the [[Apostles in the New Testament|Apostles]]. This belief was expressed by the bishops in the Creed of Nicaea, which would form the basis of what has since been known as the Niceno-Constantinopolitan Creed.<ref>{{harvnb|González|1984|p=165}}</ref>

== Nicene Creed ==
{{Main|Nicene Creed}}[[File:Nicaea icon.jpg|thumb|upright|Icon depicting [[Constantine I|the Emperor Constantine]] and the bishops of the First Council of Nicaea (325) holding the [[Niceno-Constantinopolitan Creed|Niceno–Constantinopolitan Creed of 381]]]]

The Council formulated a creed, a declaration and summary of the Christian faith. Several creeds were already in existence; many creeds were acceptable to the members of the Council, including Arius. From earliest times, various creeds served as a means of identification for Christians, as a means of inclusion and recognition, especially at baptism. In Rome, for example, the [[Apostles' Creed]] was popular, especially for use in [[Lent]] and the Easter season. In the Council of Nicaea, one specific creed was used to define the Church's faith clearly, to include those who professed it, and to exclude those who did not.

The original Nicene Creed read as follows:

{{poemquote|We believe in one God, the Father almighty,
maker of all things visible and invisible;
And in one Lord, Jesus Christ, the Son of God,
begotten from the Father, only-begotten,
that is, from the substance of the Father,
God from God, light from light,
true God from true God, begotten not made,
of one substance with the Father,
through Whom all things came into being,
things in heaven and things on earth,
Who because of us men and because of our salvation came down,
and became incarnate and became man, and suffered,
and rose again on the third day, and ascended to the heavens,
and will come to judge the living and dead,
And in the Holy Spirit.
But as for those who say, There was when He was not,
and, Before being born He was not,
and that He came into existence out of nothing,
or who assert that the Son of God is of a different hypostasis or substance,
or created, or is subject to alteration or change
– these the Catholic and apostolic Church anathematizes.<ref name="creed">{{Cite web|url=https://earlychurchtexts.com/public/creed_of_nicaea_325.htm|title=Creed of Nicaea 325 – Greek and Latin Text with English translation|website=earlychurchtexts.com}}</ref>}}The creed was amended by the [[First Council of Constantinople]] in 381.

=== Distinctive elements ===
Some distinctive elements in the Nicene Creed, perhaps from the hand of Hosius of Cordova, were added, some specifically to counter the Arian point of view.<ref name="kelly1978" /><ref>{{harvnb|Loyn|1991|p=240}}</ref>

# Jesus Christ is described as "Light from Light, true God from true God", proclaiming his divinity.
# Jesus Christ is said to be "begotten, not made", asserting that he was not a mere creature, brought into being out of nothing, but the true Son of God, brought into being "from the substance of the Father".
# He is said to be "of one substance with the Father", proclaiming that although Jesus Christ is "true God" and God the Father is also "true God", they are "of one substance". The Greek term ''homoousios'', [[Consubstantiality|consubstantial]] (i.e. of the ''same'' substance) is ascribed by Eusebius of Caesarea to Constantine who, on this particular point, may have chosen to exercise his authority. The significance of this clause, however, is ambiguous as to the extent in which Jesus Christ and God the Father are "of one substance", and the issues it raised would be seriously controverted in the future.

=== Anathemas ===
At the end of the creed came a list of [[Anathema#Early Church|anathemas]], designed to repudiate explicitly the Arians' stated claims.

# The view that "there was once when he was not" was rejected to maintain the coeternity of the Son with the Father.
# The view that he was "mutable or subject to change" was rejected to maintain that the Son just like the Father was beyond any form of weakness or corruptibility, and most importantly that he could not fall away from absolute moral perfection.

Thus, instead of a baptismal creed acceptable to both the Arians and their opponents, the Council promulgated one which was clearly opposed to Arianism and incompatible with the distinctive core of their beliefs. The text of this profession of faith is preserved in a letter of Eusebius to his congregation, in Athanasius' works, and elsewhere. The [[Homoousian]]s (from the [[Koine Greek]] word translated as "of same substance" which was condemned at the Council of Antioch in 264–268) were the most vocal of anti-Arians and were able to advance the use of the term, thus the creed was accepted by the Council.

=== Pro-Nicene leaders ===
Bishop Hosius of Cordova, one of the firm Homoousians, may well have helped bring the Council to consensus. At the time of the Council, he was the confidant of the emperor in all Church matters. Hosius stands at the head of the lists of bishops, and Athanasius ascribes to him the actual formulation of the creed. Leaders such as Eustathius of Antioch, Alexander of Alexandria, Athanasius, and [[Marcellus of Ancyra]] all adhered to the Homoousian position.

=== Arius' supporters ===
In spite of his sympathy for Arius, Eusebius of Caesarea adhered to the decisions of the Council, accepting the entire creed. The initial number of bishops supporting Arius was small perhaps only around 18. After a month of discussion, on 19 June, there were only two left: Theonas of Marmarica in Libya and Secundus of Ptolemais. Maris of Chalcedon, who initially supported Arianism, agreed to the whole creed but not the anathemas.<ref>{{Cite book |last=Davis |first=Leo |title=The First Seven Ecumenical Councils (325–787) Their History and Theology |pages=63}}</ref> Similarly, Eusebius of Nicomedia and Theognis of Nice also agreed, except for certain statements.

=== Exiled ===
The emperor carried out his earlier statement: everybody who refused to endorse the creed would be [[exile]]d. Arius, Theonas, and Secundus refused to adhere to the creed and were thus exiled to [[Illyria]], in addition to being [[excommunication|excommunicated]]. The works of Arius were ordered to be confiscated and [[book burning|consigned to the flames]],<ref name=EB1911/> while his supporters were considered as "enemies of Christianity".{{sfn|Schaff|Schaff|1910|loc=Section 120}} Nevertheless, the controversy continued in various parts of the empire.<ref>{{harvnb|Lutz von Padberg|1998|p=26}}</ref>

== Separation of Easter computation from Jewish calendar ==
The feast of Easter is linked to the Jewish [[Passover]] and Feast of Unleavened Bread, as Christians believe that the [[Crucifixion of Jesus|crucifixion]] and [[Resurrection of Jesus|resurrection]] of Jesus occurred at the time of those observances. As early as [[Pope Sixtus I]] in the 2nd century, some Christians had set Easter to a Sunday in the lunar month of [[Nisan]]. To determine which lunar month was to be designated as Nisan, Christians relied on the Jewish community. By the late 3rd century some Christians began to express dissatisfaction with what they took to be the disorderly state of the [[Hebrew calendar|Jewish calendar]]. They argued that contemporary Jews were identifying the wrong lunar month as the month of Nisan, choosing a month whose 14th day fell before the [[March equinox|spring equinox]].{{Sfn|Anatolius|loc=Book 7, Chapter 33}}

Christians, these thinkers argued, should abandon the custom of relying on Jewish informants and instead do their own computations to determine which month should be styled Nisan, setting Easter within this independently computed, Christian Nisan, which would always locate the festival after the equinox. They justified this break with tradition by arguing that it was in fact the contemporary Jewish calendar that had broken with tradition by ignoring the equinox and that in former times the 14th of Nisan had never preceded the equinox.{{Sfn|Chronicon Paschale}} Others felt that the customary practice of reliance on the Jewish calendar should continue, even if the Jewish computations were in error from a Christian point of view.{{Sfn|Panarion|loc=Book 3, Chapter 1, Section 10}}

The controversy between those who argued for independent computations and those who argued for continued reliance on the Jewish calendar was formally resolved by the Council, which endorsed the independent procedure that had been in use for some time at Rome and Alexandria. Easter was henceforward to be a Sunday in a lunar month chosen according to Christian criteria—in effect, a Christian Nisan—not in the month of Nisan as defined by Jews.<ref name="ReferenceB" /> Those who argued for continued reliance on the Jewish calendar (called "protopaschites" by later historians) were urged to come around to the majority position. That they did not all immediately do so is revealed by the existence of sermons,{{Sfn|Chrysostom|p=47}} canons,{{Sfn|SEC|p=594}} and tracts{{Sfn|Panarion|loc=Book 3, Chapter 1}} written against the protopaschite practice in the late 4th century.

These two rules—independence of the Jewish calendar and worldwide uniformity—were the only rules for Easter explicitly laid down by the Council. No details for the computation were specified; these were worked out in practice, a process that took centuries and [[Easter controversy|generated numerous controversies]], some of which remain unresolved. In particular, the Council did not seem to decree that Easter must fall on Sunday.{{Sfn|Sozomen|loc=Book 7, Chapter 18}} This was unnecessary as it resolved against the ''Quartodecimani'', who celebrated on any day of the week, in favour of the Churches who postponed the celebration to the following Sunday. See the extract from the ''Letter of the Council of Nicaea to the Egyptian Church'', cited above.

Nor did the Council decree that Easter must never coincide with Nisan 15 (the first Day of Unleavened Bread, now commonly called "Passover") in the Hebrew calendar. The Finnish Orthodox Church explains, "According to the definition of the Council of Nicaea in 325, Pascha is celebrated on the first Sunday after the full moon following the vernal equinox, but always after the Jewish Passover. The date of the vernal equinox was then defined as March 21."<ref>{{cite web|url=http://orthochristian.com/157576.html|last=Finnish Orthodox Church|title=Finnish church resolves to continue using Gregorian Paschalion|date=30 November 2023|accessdate=9 March 2024}}</ref> L'Huillier notes the success of this strategy - Orthodox Easter has never preceded Passover.{{Sfn|L'Huillier|1996|p=25}}

== Melitian schism ==
{{Main|Melitians}}

The suppression of the Melitian schism, an early breakaway sect, was another important matter that came before the Council of Nicaea. Melitius, it was decided, should remain in his own city of [[Lycopolis]] in Egypt but without exercising authority or the power to ordain new clergy; he was forbidden to go into the environs of the town or to enter another diocese for the purpose of ordaining its subjects. Melitius retained his episcopal title, but the ecclesiastics ordained by him were to receive again the [[Christian laying on of hands|laying on of hands]], the ordinations performed by Melitius being therefore regarded as invalid. Clergy ordained by Melitius were ordered to yield precedence to those ordained by Alexander, and they were not to do anything without the consent of Bishop Alexander.<ref>{{harvnb|Leclercq|1911a}}</ref>

In the event of the death of a non-Melitian bishop or ecclesiastic, the vacant [[Episcopal see|see]] might be given to a Melitian, provided he was worthy and the popular election were ratified by Alexander. Melitius' episcopal rights and prerogatives were taken from him. These mild measures, however, were in vain; the Melitians joined the Arians and caused more dissension than ever, being among the worst enemies of Athanasius. The Melitians ultimately died out around the middle of the 5th century.

== Promulgation of canon law ==
{{canon law}}
{{Main|Canon law|Collections of ancient canons|Promulgation (Catholic canon law)}}
The Council promulgated twenty new church laws, called ''[[Canon (canon law)|canons]]'' (though the exact number is subject to debate), that is, rules of discipline. The twenty as listed in the works of [[Nicene and Post-Nicene Fathers]] are as follows:<ref>{{harvnb|Canons}}</ref>

# prohibition of self-[[castration]] for clergy
# establishment of a minimum term for [[catechumen]]s (persons studying for baptism)
# prohibition of a man and a woman who have both taken [[Religious vows|vows of chastity]] to live together in a chaste and non-legalized partnership (the so called ''virgines subintroductae'', who practiced [[syneisaktism]])
# ordination of a bishop in the presence of at least three provincial bishops<ref name=EB1911/> and confirmation by the [[metropolitan bishop]]
# provision for two provincial [[synod]]s to be held annually
# confirmation of ancient customs giving jurisdiction over large regions to the bishops of Alexandria, Rome, and Antioch
# recognition of the honorary rights of the see of [[Jerusalem in Christianity|Jerusalem]]
# provision for agreement with the [[Novatianism|Novatianists]], an early sect
# elders who had been ordained without sufficient examination were not to be recognized
# elders who had lapsed but had not been found out were to be deposed
# mercy was enjoined toward those who had lapsed without compulsion, even though it was recognized that they did not deserve it
# those who had left the military but later sought out to be restored to their military position were to be excommunicated; depending on the sincerity of their repentance, they could be readmitted to communion earlier
# those who were fulfilling [[penance]] could receive communion if they were dying, but if they got well again, they were to finish their penance
# catechumens who lapsed were to have three years as hearers before being allowed to become catechumens again
# bishops, presbyters, and deacons were not to wander into neighboring cities to officiate
# clergy who refused to return to their home church were to be excommunicated, and the ordinations of those who were ordained by these wandering clergy were to be considered null and void
# prohibition of [[usury]] among the clergy
# precedence of bishops and presbyters before deacons in receiving the [[Eucharist]] (Holy Communion)
# declaration of the invalidity of [[baptism]] by [[Paul of Samosata|Paulian heretics]]
# prohibition of kneeling on Sundays and during the [[Pentecost]] (the fifty days commencing on Easter). Standing was the normative posture for prayer at this time, as it still is among the Eastern Christians. Kneeling was considered most appropriate to penitential prayer, as distinct from the festive nature of Eastertide and its remembrance every Sunday. The canon was designed only to ensure uniformity of practice at the designated times.

== Effects ==
[[File:COUNCIL OF NICEA Fresco in the Sistine Salon Vatican t.jpg|thumb|upright=1.25|A fresco depicting the First Council of Nicaea at the [[Vatican City|Vatican]]'s Sixtine Salon]]
In the short-term, the Council did not completely solve the problems it was convened to discuss, and a period of conflict and upheaval continued for some time. Constantine was succeeded by two Arian emperors in the Eastern Empire: his son, [[Constantius II]], and [[Valens]]. Valens could not resolve the outstanding ecclesiastical issues and unsuccessfully confronted [[Basil of Caesarea|St. Basil]] over the Nicene Creed.<ref>{{cite magazine |date=February 1968|title=Heroes of the Fourth Century |magazine=Word Magazine |publisher=Antiochian Orthodox Christian Archdiocese of North America |pages=15–19 |url=http://www.orthodoxresearchinstitute.org/articles/patrology/heroes_of_4th_century_pt2.htm}}</ref>

Pagan powers within the empire sought to maintain and at times re-establish paganism into the seat of the emperor (see [[Arbogast (magister militum)|Arbogast]] and [[Julian the Apostate]]). Arians and Meletians soon regained nearly all of the rights they had lost, and consequently Arianism continued to spread and be a subject of debate within the Church during the remainder of the 4th century. Almost immediately, Eusebius of Nicomedia, an Arian bishop and cousin to Constantine I, used his influence at court to sway Constantine's favor from the proto-orthodox Nicene bishops to the Arians.<ref name="Davis 1983 77">{{harvnb|Davis|1983|p=77}}</ref>

Eustathius of Antioch was deposed and exiled in 330. Athanasius, who had succeeded Alexander as Bishop of Alexandria, was deposed by the [[First Synod of Tyre]] in 335, and Marcellus of Ancyra followed him in 336. Arius returned to Constantinople to be readmitted into the Church but died shortly before he could be received. Constantine died the next year, after finally receiving baptism from Arian Bishop Eusebius of Nicomedia, and "with his passing the first round in the battle after the Council of Nicaea was ended".<ref name="Davis 1983 77" />

== Role of Constantine ==
{{See also|Constantine the Great and Christianity}}
Christianity had only recently been legalised in the empire, the [[Diocletianic Persecution]] having ended in 311 under [[Galerius]]. Although Galerius stopped the Persecution, Christianity was not legally protected until 313, when the emperors Constantine and [[Licinius]] agreed to what became known as the [[Edict of Milan]], guaranteeing Christians legal protection and tolerance. However, Nicene Christianity did not become the [[state religion]] of the [[Roman Empire]] until the [[Edict of Thessalonica]] in 380. In the meantime, paganism remained legal and present in public affairs. Constantine's coinage and other official motifs, until the Council of Nicaea, had affiliated him with the pagan cult of [[Sol Invictus]]. At first, Constantine encouraged the construction of new temples<ref>Gerberding, R. and J. H. Moran Cruz, ''Medieval Worlds'' (New York: Houghton Mifflin Company, 2004) p. 28.</ref> and tolerated [[Religion in ancient Rome#Sacrifice|traditional sacrifices]].<ref>Peter Brown, ''The Rise of Christendom'' 2nd edition (Oxford, Blackwell Publishing, 2003) p. 60.</ref> Later in his reign, he gave orders for the [[pillaging]] and the tearing down of [[Roman temple]]s.<ref>R. MacMullen, ''Christianizing The Roman Empire A.D. 100–400'', Yale University Press, 1984, {{ISBN|0-300-03642-6}}</ref><ref>"A History of the Church", [[Philip Hughes (historian)|Philip Hughes]], Sheed & Ward, rev ed 1949, vol I chapter 6.[http://www.ewtn.com/library/CHISTORY/HUGHHIST.TXT]</ref><ref>Eusebius Pamphilius and [[Philip Schaff|Schaff, Philip]] (Editor) and McGiffert, Rev. Arthur Cushman, PhD (Translator) [http://www.ccel.org/ccel/schaff/npnf201.txt ''NPNF2-01. Eusebius Pamphilius: Church History, Life of Constantine, Oration in Praise of Constantine''] {{Webarchive|url=https://web.archive.org/web/20180417033355/http://www.ccel.org/ccel/schaff/npnf201.txt |date=17 April 2018 }} quote: "he razed to their foundations those of them which had been the chief objects of superstitious reverence".</ref>

Constantine's role regarding Nicaea was that of supreme civil leader and authority in the empire. As Emperor, the responsibility for maintaining civil order was his, and he sought that the Church be of one mind and at peace. When first informed of the unrest in Alexandria due to the Arian disputes, he was "greatly troubled" and, "rebuked" both Arius and Bishop [[Pope Alexander I of Alexandria|Alexander]] for originating the disturbance and allowing it to become public.<ref name="sozomen1">{{harvnb|Sozomen|loc=Book 1, Chapter 16}}</ref> Aware also of "the diversity of opinion" regarding the celebration of Easter and hoping to settle both issues, he sent the "honored" Bishop [[Hosius of Corduba|Hosius of Cordova]] (Hispania) to form a local church council and "reconcile those who were divided".<ref name="sozomen1" /> When that embassy failed, he turned to summoning a synod at Nicaea, inviting "the most eminent men of the churches in every country".<ref>{{harvnb|Sozomen|loc=Book 1, Chapter 17}}</ref>

Constantine assisted in assembling the Council by arranging that travel expenses to and from the bishops' [[episcopal see]]s, as well as lodging at Nicaea, be covered out of public funds.<ref name="theodoret1">{{harvnb|Theodoret|loc=Book 1, Chapter 6}}</ref> He also provided and furnished a "great hall ... in the palace" as a place for discussion so that his guests "should be treated with becoming dignity".<ref name="theodoret1" /> In addressing the opening of the Council, he "exhorted the Bishops to unanimity and concord" and called on them to follow the Holy Scriptures with: "Let, then, all contentious disputation be discarded; and let us seek in the divinely-inspired word the solution of the questions at issue."<ref name="theodoret1" />

Thereupon, the debate about Arius and church doctrine began. "The emperor gave patient attention to the speeches of both parties" and "deferred" to the decision of the bishops.<ref>{{harvnb|Sozomen|loc=Book 1, Chapter 20}}</ref> The bishops first pronounced Arius' teachings to be anathema, formulating the creed as a statement of correct doctrine. When Arius and two followers refused to agree, the bishops pronounced clerical judgement by excommunicating them from the Church. Respecting the clerical decision, and seeing the threat of continued unrest, Constantine also pronounced civil judgement, banishing them into exile. This was the beginning of the practice of using secular power to establish doctrinal orthodoxy within Christianity, an example followed by all later Christian emperors, which led to a circle of Christian violence, and of Christian resistance couched in terms of martyrdom.<ref>There is no crime for those who have Christ; religious violence in the Roman Empire. Michael Gaddis. University of California Press 2005. p. 340.{{ISBN|978-0-520-24104-6}}</ref>

== Misconceptions ==

=== Biblical canon ===
{{Main|Development of the Christian Biblical canon}}

There is no record of any discussion of the [[biblical canon]] at the council.<ref>John Meade, "[https://ps.edu/council-nicaea-biblical-canon/ The Council of Nicaea and the Biblical Canon]" and {{harvnb|Ehrman|2004|pp=15–16, 23, 93}}</ref> The development of the biblical canon was nearly complete (with exceptions known as the [[Antilegomena]], written texts whose authenticity or value is disputed) by the time the [[Muratorian fragment]] was written.<ref>{{harvnb|McDonald & Sanders|2002|loc=Apendex D2, Note 19}}</ref> The main source of the idea that the canon was created at the Council of Nicaea seems to be [[Voltaire]], who popularised a story that the canon was determined by placing all the competing books on an altar during the Council and then keeping the ones that did not fall off. The original source of this "fictitious anecdote" is the ''[[Synodicon Vetus]]'',<ref>{{cite book |title=Ecce homo!: An Eighteenth Century Life of Jesus |others=Critical Edition and Revision of George Houston's Translation from the French |url=https://books.google.com/books?id=ZrDnBQAAQBAJ |author=Paul T. d' Holbach |author-link=Baron d'Holbach |editor=Andrew Hunwick |year=1995 |location=Berlin, New York |publisher=Walter de Gruyter & Co. |isbn=978-3-11-081141-4 |pages=48–49}}</ref> a pseudo-historical account of early Church councils from 887.<ref>A summary of the case can be found at [http://www.tertullian.org/rpearse/nicaea.html The Council of Nicaea and the Bible].</ref>

In 331, [[Fifty Bibles of Constantine|Constantine commissioned fifty Bibles]] for the use of the Bishop of Constantinople, but little else is known (in fact, it is not even certain whether his request was for fifty copies of the entire Old and New Testaments, only the New Testament, or merely the Gospels). Some scholars believe that this request provided motivation for canon lists. In [[Jerome]]'s ''Prologue to Judith'', he claims that the [[Book of Judith]] was "found by the Nicene Council to have been counted among the number of the Sacred Scriptures".<ref>{{harvnb|Preface to Tobit and Judith}}</ref> However, modern scholars such as Edmon Gallagher have doubted that this indicates any canon selection in the council.<ref>{{cite web |url=https://www.academia.edu/14345165 |title="Why Did Jerome Translate Tobit and Judith?" Harvard Theological Review 108 (2015): 356–75.|last=Gallagher |first=Edmon|date=2015 |website=academia.edu |page=369-370|access-date= November 26, 2022}}</ref>

=== Trinity ===
The Council of Nicaea dealt primarily with the issue of the [[deity of Christ]]. The term "Trinity" was already in use, with the earliest existing reference being by [[Theophilus of Antioch]] (AD 115–181), referring to God, the Logos, and Sophia<ref>{{Cite web |title=Philip Schaff: Fathers of the Second Century: 0107=101 – Christian Classics Ethereal Library |url=https://ccel.org/ccel/schaff/anf02/anf02/Page_101.html |access-date=2023-04-27 |website=ccel.org}}</ref> (Father, Son and Holy Spirit, as the Holy Spirit was referred to by several Church fathers), though many scholars believe that the way the term was used indicates that it was known previously to his readers. Also, over a century before, the term "[[Trinity]]" ({{lang|grc|Τριάς}} in Greek; {{lang|la|trinitas}} in Latin) was used in the writings of [[Origen]] and [[Tertullian]], and a general notion of a "divine three", in some sense, was expressed in the 2nd-century writings of [[Polycarp]], [[Ignatius of Antioch|Ignatius]], and [[Justin Martyr]]. In Nicaea, questions regarding the Holy Spirit were left largely unaddressed until after the relationship between the Father and the Son was settled around the year 362.<ref>{{harvnb|Fairbairn|2009|pp=46–47}}</ref> The doctrine in a more full-fledged form was not formulated until the [[Council of Constantinople (381)|Council of Constantinople]] in 381<ref>{{harvnb|Socrates|loc=Book 2, Chapter 41}}</ref> and a final form formulated primarily by [[Gregory of Nyssa]].<ref>{{Cite book|last1=Schaff|first1=Philip|url=https://books.google.com/books?id=AIAXAAAAYAAJ&pg=PA477|title=A Select Library of Nicene and Post-Nicene Fathers of the Christian Church: Gregory of Nyssa: Dogmatic treatises, etc. 1893|last2=Wace|first2=Henry|date=1893|publisher=Christian literature Company|language=en}}</ref>

=== Constantine ===
While Constantine had sought a unified church after the Council, he did not force the [[homoousian]] view of Christ's nature on the council. Constantine did not commission any Bibles at the Council. Despite Constantine's sympathetic interest in the Church, he was not baptized until some 11 or 12 years after the council, putting off baptism as long as he did so as to be absolved from as much sin as possible.<ref>Marilena Amerise, 'Il battesimo di Costantino il Grande."</ref>

== Disputed matters ==
{{See also|Primacy of the Roman pontiff|East–West Schism}}

According to Protestant theologian [[Philip Schaff]]: "The Nicene fathers passed this canon not as introducing anything new, but merely as confirming an existing relation on the basis of church tradition; and that, with special reference to Alexandria, on account of the troubles existing there. Rome was named only for illustration; and Antioch and all the other eparchies or provinces were secured their admitted rights. The [[Episcopal see|bishoprics]] of [[Early centers of Christianity#Alexandria|Alexandria]], [[Early centers of Christianity#Rome|Rome]], and [[Early centers of Christianity#Antioch|Antioch]] were placed substantially on equal footing." Thus, according to Schaff, the Bishop of Alexandria was to have jurisdiction over the provinces of Egypt, Libya and the Pentapolis, just as the Bishop of Rome had authority "with reference to his own diocese."<ref>{{harvnb|Schaff|Schaff|1910|pp=275–276}}</ref>

However, according to Fr. James F. Loughlin, there is an alternative Catholic interpretation. It involves five different arguments "drawn respectively from the grammatical structure of the sentence, from the logical sequence of ideas, from Catholic analogy, from comparison with the process of formation of the Byzantine Patriarchate, and from the authority of the ancients"<ref name="Loughlin 1880">{{harvnb|Loughlin|1880}}</ref> in favor of an alternative understanding of the canon. According to this interpretation, the canon shows the role the Bishop of Rome had when he, by his authority, confirmed the jurisdiction of the other patriarchs—an interpretation which is in line with the Catholic understanding of the Pope. Thus, the Bishop of Alexandria presided over Egypt, Libya and the Pentapolis,<ref name=EB1911/> while the Bishop of Antioch "enjoyed a similar authority throughout the great diocese of Oriens," and all by the authority of the Bishop of Rome. To Loughlin, that was the only possible reason to invoke the custom of a Roman Bishop in a matter related to the two metropolitan bishops in Alexandria and Antioch.<ref name="Loughlin 1880" />

However, Protestant and Catholic interpretations have historically assumed that some or all of the bishops identified in the canon were presiding over their own dioceses at the time of the Council—the Bishop of Rome over the Diocese of Italy, as Schaff suggested, the Bishop of Antioch over the Diocese of Oriens, as Loughlin suggested, and the Bishop of Alexandria over the Diocese of Egypt, as suggested by [[Karl Josef von Hefele]]. According to Hefele, the Council had assigned to Alexandria, "the whole (civil) Diocese of Egypt."<ref>{{cite book|last1=von Hefele|first1=Karl|title=Conciliengeschichte, v. 1|date=1855|publisher=Herder|location=Freiburg im Breisgau, Baden-Württemberg, Germany|page=373}}</ref> Yet those assumptions have since been proven false. At the time of the Council, the [[Diocese of Egypt]] did exist but was known as the Diocese of Alexandria, so the Council could have assigned it to Alexandria. Antioch and Alexandria were both located within the civil Diocese of Oriens, Antioch being the chief metropolis, but neither administered the whole. Likewise, Rome and Milan were both located within the civil Diocese of Italy, Milan being the chief metropolis.<ref>{{cite web|last1=Athanasius of Alexandria|title=Historia Arianorum, Part IV, chapter 36|url=http://www.newadvent.org/fathers/28154.htm|access-date=22 June 2016}}</ref><ref>{{cite web|last1=Athanasius of Alexandria|title=Apologia de Fuga, chapter 4|url=http://www.newadvent.org/fathers/2814.htm|access-date=22 June 2016}}</ref>

This geographic issue related to Canon 6 was highlighted by Protestant writer Timothy F. Kauffman, as a correction to the anachronism created by the assumption that each bishop was already presiding over a whole diocese at the time of the Council.<ref>{{cite journal|last1=Kauffman|first1=Timothy F.|title=Nicæa and the Roman Precedent|journal=The Trinity Review|date=May–June 2016|issue=334, 335|url=http://trinityfoundation.org/PDF/The%20Trinity%20Review%20334%20Nica%20and%20the%20Roman%20Precedent%20Kauffman.pdf |archive-url=https://web.archive.org/web/20160812085230/http://trinityfoundation.org/PDF/The%20Trinity%20Review%20334%20Nica%20and%20the%20Roman%20Precedent%20Kauffman.pdf |archive-date=2016-08-12 |url-status=live|access-date=22 June 2016}}</ref> According to Kauffman, since Milan and Rome were both located within the Diocese of Italy, and Antioch and Alexandria were both located within the Diocese of Oriens, a relevant and "structural congruency" between Rome and Alexandria was readily apparent to the gathered bishops: both had been made to share a diocese of which neither was the chief metropolis. Rome's jurisdiction within Italy had been defined in terms of several of the city's adjacent provinces since Diocletian's reordering of the empire in 293, as the earliest Latin version of the canon indicates.<ref>{{cite book|last1=Turner|first1=Cuthberthus Hamilton|title=Ecclesiae Occidentalis monumenta iuris antiquissima, vol. 1|date=1899|publisher=Oxonii, E Typographeo Clarendoniano|page=120}}</ref>

That provincial arrangement of Roman and Milanese jurisdiction within Italy therefore was a relevant precedent, and provided an administrative solution to the problem facing the Council—namely, how to define Alexandrian and Antiochian jurisdiction within the Diocese of Oriens. In canon 6, the Council left most of the diocese under Antioch's jurisdiction, and assigned a few provinces of the diocese to Alexandria, "since the like is customary for the Bishop of Rome also."<ref>{{cite web|last1=First Council of Nicæa|title=Canon 6|url=http://www.newadvent.org/fathers/3801.htm|website=The First Council of Nicæa|access-date=22 June 2016}}</ref>

== See also ==
{{Wikiversity|Council of Nicea (325 A.D.)}}
* [[Ancient church councils (pre-ecumenical)]] – church councils before the First Council of Nicaea

== References ==
{{Reflist|30em}}

== Bibliography ==

=== Primary sources ===
Note: NPNF2 = {{citation |editor1-last=Schaff |editor1-first=Philip |editor-link1=Philip Schaff |editor2-last=Wace |editor2-first=Henry |title=Nicene and Post-Nicene Fathers |url=http://www.ccel.org/fathers.html |series=Second Series |publisher= Christian Classics Ethereal Library |ref=none}}, see also [[Nicene and Post-Nicene Fathers]]
* {{citation|title=Eusebius Pamphilius: Church History, Life of Constantine, Oration in Praise of Constantine|url=http://www.ccel.org/ccel/schaff/npnf201.iii.html|series=NPNF2|volume=1|access-date=2014-02-24}}
** {{citation|author=Anatolius of Laodicea|author-link=Anatolius of Laodicea|title=The Ecclesiastical History of Eusebius|chapter-url=http://www.ccel.org/ccel/schaff/npnf201.iii.xii.xxxiii.html|chapter=''Paschal Canons'' quoted by Eusebius|ref={{harvid|Anatolius}}}}
** {{citation|author=Eusebius Pamphilius|author-link=Eusebius|title=The Life of Constantine [Vita Constantini].|url=http://www.ccel.org/ccel/schaff/npnf201.iv.vi.html|ref={{harvid|Vita Constantini}}}}
* {{citation|title=Socrates and Sozomenus Ecclesiastical Histories|url=http://www.ccel.org/ccel/schaff/npnf202.html|series=NPNF2|volume=2|ref={{harvid|Socrates}}}}
** {{citation|author=Socrates of Constantinople|author-link=Socrates of Constantinople|title=The Ecclesiastical History of Socrates Scholasticus|url=http://www.ccel.org/ccel/schaff/npnf202.ii.html|access-date=2014-02-24}}
** {{citation|author=Sozomen|author-link=Sozomen|title=The Ecclesiastical History of Sozomen|url=http://www.ccel.org/ccel/schaff/npnf202.iii.html}}
* {{citation|title=Theodoret, Jerome, Gennadius, and Rufinus: Historical Writings|url=http://www.ccel.org/ccel/schaff/npnf202.iii.html|series=NPNF2|volume=3|access-date=2014-02-24}}
** {{citation|author=Constantine the Great|author-link=Constantine the Great|title=The Ecclesiastical History of Theodoret|chapter-url=http://www.ccel.org/ccel/schaff/npnf203.iv.viii.i.x.html|chapter=''Constantinus Augustus to the Churches'' quoted by Theodoret|access-date=2014-02-24}}
** {{citation|author=Eustathius of Antioch|author-link=Eustathius of Antioch|title=The Ecclesiastical History of Theodoret|chapter-url=http://www.ccel.org/ccel/schaff/npnf203/Page_45.html|chapter=''A Letter to the African Bishops'' quoted by Theodoret|access-date=2014-02-24}}
** {{citation|author=Theodoret of Cyrus|author-link=Theodoret of Cyrus|title=The Ecclesiastical History of Theodoret|url=http://www.ccel.org/ccel/schaff/npnf203.iv.viii.html|ref={{harvid|Theodoret}}}}
* {{citation|title=Athanasius: Select Works and Letters|url=http://www.ccel.org/ccel/schaff/npnf204.html|series=NPNF2|volume=4|access-date=2014-02-24}}
** {{citation|author=Athanasius of Alexandria|author-link=Athanasius of Alexandria|title=De Decretis|url=http://www.ccel.org/ccel/schaff/npnf204.xiv.ii.html|trans-title=Defence of the Nicene Definition|access-date=2014-02-24}}
** {{citation|author=Athanasius of Alexandria|author-link=Athanasius of Alexandria|title=Ad Afros Epistola Synodica|url=http://www.ccel.org/ccel/schaff/npnf204.xxiv.html|trans-title=Synodal Letter to the Bishops of Africa|ref={{harvid|Ad Afros Epistola Synodica}}}}
** {{citation|author=Eusebius Pamphilus|author-link=Eusebius Pamphilus|title=Letter of Eusebius of Cæsarea to the people of his Diocese|url=http://www.ccel.org/ccel/schaff/npnf204.ix.ii.html|access-date=2014-02-24}}
* {{citation|title=Jerome: The Principal Works of St. Jerome|url=http://www.ccel.org/ccel/schaff/npnf206|series=NPNF2|volume=6|access-date=2014-02-24}}
** {{citation|author=Jerome|author-link=Jerome|title=Prefaces to the Books of Tobit and Judith|url=http://www.ccel.org/ccel/schaff/npnf206.vii.iii.xx.html|ref={{harvid|Preface to Tobit and Judith}}}}
* {{citation|title=The Seven Ecumenical Councils|url=http://www.ccel.org/ccel/schaff/npnf214.html|series=NPNF2|volume=14|ref={{harvid|SEC}}}}
** {{citation|title=The Nicene Creed|url=http://www.ccel.org/ccel/schaff/npnf214.vii.iii.html|access-date=2014-02-24}}
** {{citation|title=The Canons of the 318 Holy Fathers Assembled in the City of Nice, in Bithynia|url=http://www.ccel.org/ccel/schaff/npnf214.vii.vi.i.html|ref={{harvid|Canons}}}}
** {{citation|author=Athanasius of Alexandria|author-link=Athanasius of Alexandria|title=The Synodal Letter|url=http://www.ccel.org/ccel/schaff/npnf214.vii.ix.html|access-date=2014-02-24}}
** {{citation|author=Constantine the Great|author-link=Constantine the Great|title=The Life of Constantine|chapter-url=http://www.ccel.org/ccel/schaff/npnf214.vii.x.html|chapter=''On the Keeping of Easter'' quoted by Eusebius|ref={{harvid|On the Keeping of Easter}}}}
* {{citation|title=Chronicon Paschale|trans-title=Paschal Chronicle|ref={{harvid|Chronicon Paschale}}|title-link=Chronicon Paschale}}
* {{citation|title=Pentecostarion|url=http://www.anastasis.org.uk/FathVes.htm|access-date=22 February 2014|date=3 November 2008|publisher=Archdiocese of Thyateira and Great Britain|ref={{harvid|Pentecostarion}}|archive-url=https://web.archive.org/web/20160430004400/http://anastasis.org.uk/FathVes.htm|archive-date=30 April 2016|url-status=dead}}
* {{citation|last1=Chrysostom|first1=John|author-link1=John Chrysostom|last2=Harkins|first2=Paul W (trans)|title=Discourses Against Judaizing Christians|url=https://books.google.com/books?id=JXtTCq7V_0MC|series=The Fathers of the Church|volume=68|date=1 April 2010|publisher=Catholic University of America Press|isbn=978-0-8132-1168-8|ref={{harvid|Chrysostom}}}}
* {{citation|author1=Epiphanius of Salamis|author-link1=Epiphanius of Salamis|last2=Williams|first2=Frank (trans)|title=The Panarion of Epiphanius of Salamis|url=https://books.google.com/books?id=DAP-uJTfc84C|year=1994|publisher=Brill|location=Leiden |isbn=90-04-09898-4|ref={{harvid|Panarion}}}}
* {{citation|author=Hilary of Poitiers|author-link=Hilary of Poitiers|title=Contra Constantium Augustum Liber|trans-title=A Book Against the Emperor Constantine|ref={{harvid|Contra Constantium Augustum Liber}}}}
* {{citation|author=Jerome|author-link=Jerome|title=Temporum Liber|trans-title=The Book of Times|ref={{harvid|Temporum Liber}}}}
* {{citation|author1=Photios I of Constantinople|author-link1=Photios I of Constantinople|last2=Walford|first2=Edward (trans)|title=Epitome of the Ecclesiastical History of Philostorgius, Compiled by Photius, Patriarch of Constantinople |url=http://www.tertullian.org/fathers/philostorgius.htm|ref={{harvid|Photius I}}}}

=== Secondary sources ===
{{Div col|colwidth=30em}}
* {{citation|last=Anatolios|first=Khaled|title=Retrieving Nicaea: The Development and Meaning of Trinitarian Doctrine|url=https://books.google.com/books?id=O6QOmQEACAAJ|date=2011|publisher=Baker Publishing Group|location=Grand Rapids|isbn=978-0-8010-3132-8}}
* {{citation|last=Athanasius |first=(Patriarch of Alexandria) |title=Select treatises of St. Athanasius in controversy with the Arians, Volume 3 |others=Translator and Editor John Henry Newman |publisher=Longmans, Green and co. |date=1920 |ref={{harvid|Athanasius |Newman |1920}} }}
* {{citation |last=Atiya |first=Aziz S. |title=The Coptic Encyclopedia |location=New York |publisher=Macmillan Publishing Company |date=1991 |isbn=0-02-897025-X}}
* {{citation|last=Ayers|first=Lewis|author-link=Lewis Ayres|title=Nicaea and Its Legacy|url=https://books.google.com/books?id=CYbDjXRz5-0C|date=2006|publisher=Oxford University Press|location=New York|isbn=978-0-19-875505-0|access-date=2014-02-24}}
* {{citation|last=Barnes|first=Timothy David|author-link=Timothy David Barnes|title=Constantine and Eusebius|url=https://books.google.com/books?id=fX1oAAAAMAAJ|year=1981|publisher=Harvard University Press|location=Cambridge|isbn=978-0-674-16530-4|access-date=2014-02-24}}
* {{citation|last=Carroll|first=Warren|title=The Building of Christendom|url=https://books.google.com/books?id=5nXYAAAAMAAJ|date=1987|publisher=Christendom College Press|location=Front Royal|isbn=978-0-931888-24-3|access-date=2014-02-24}}
* {{citation|last=Danker|first=Frederick William|author-link=Frederick William Danker|title=A Greek-English Lexicon of the New Testament and Other Early Christian Literature|url=https://books.google.com/books?id=hd7bZxvlbFsC|edition=Third|year=2000|publisher=University of Chicago Press|location=Chicago|isbn=978-0-226-03933-6|chapter=οἰκουμένη|access-date=2014-02-24}}
* {{citation|last=Davis|first=Leo Donald|title=The First Seven Ecumenical Councils (325–787)|url=https://books.google.com/books?id=fMhzlnY0P0QC|year=1983|publisher=Liturgical Press|location=Collegeville|isbn=978-0-8146-5616-7|access-date=2014-02-24}}
* {{Cite book|last=Edwards|first=Mark|year=2009|title=Catholicity and Heresy in the Early Church|publisher=Ashgate|url=https://books.google.com/books?id=z9acTl-jAkAC|isbn=978-0754662914}}
* {{citation|last=Ehrman|first=Bart|author-link=Bart Ehrman|title=Truth and Fiction in the Da Vinci Code|year=2004|publisher=Oxford University Press|isbn=978-1-280-84545-1}}
* {{citation|last=Fairbairn|first=Donald|author-link=Donald Fairbairn|title=Life in the Trinity|url=https://books.google.com/books?id=13jIWO-6LgYC|date=2009|publisher=InterVarsity Press|location=Downers Grove|isbn=978-0-8308-3873-8|access-date=2014-02-24}}
* {{citation|title=Patrum nicaenorum nomina Latine, Graece, Coptice, Syriace, Arabice, Armeniace|edition=2nd|year=1995|publisher=Teubner|location=Stuttgart|editor-last=Gelzer|editor-first=Heinrich|editor-link=Heinrich Gelzer|editor2-last=Hilgenfeld|editor2-first=Henricus|editor3-last=Cuntz|editor3-first=Otto|trans-title=The names of the Fathers at Nicaea in Latin, in Greek, Coptic, Syriac, Arabic, Armenian|ref={{harvid|Patrum nicaenorum}}}}
* {{citation|last=González|first=Justo L|author-link=Justo L. González|title=The Story of Christianity|url=https://books.google.com/books?id=mN5UPgAACAAJ|volume=1|year=1984|publisher=Prince Press|location=Peabody|isbn=978-1-56563-522-7|access-date=2014-02-24}}
* {{citation|last=Kelhoffer|first=James A|year=2011|title=The Search for Confessors at the Council of Nicaea|journal=Journal of Early Christian Studies|volume=19|issue=4|pages=589–599|issn=1086-3184|doi=10.1353/earl.2011.0053|s2cid=159876770|url=http://uu.diva-portal.org/smash/get/diva2:385548/FULLTEXT01}}
* {{citation|last=Kelly|first=J N D|author-link=John Norman Davidson Kelly|title=Early Christian Doctrine|url=https://books.google.com/books?id=cfY-UCywuD4C|date=1978|publisher=HarperCollins|location=San Francisco|isbn=978-0-06-064334-8|access-date=2014-02-24}}
* {{citation|last=Kelly|first=J N D|author-link=John Norman Davidson Kelly|title=Early Christian Creeds|url=https://books.google.com/books?id=UlN2QgAACAAJ|year=1981|publisher=Addison-Wesley Longman Limited|location=Harlow|isbn=978-0-582-49219-6|access-date=2014-02-24}}
* {{citation|last=Kieckhefer|first=Richard|title=Dictionary of the Middle Ages|url=https://books.google.com/books?id=EZEYAAAAIAAJ|volume=9|year=1989|publisher=Charles Scribner's Sons|isbn=978-0-684-18278-0|chapter=Papacy|editor-last=Strayer|editor-first=Joseph Reese|editor-link=Joseph Strayer|access-date=2014-02-24}}
* {{citation|last=L'Huillier|first=Peter|author-link=Peter L'Huillier|title=The Church of the Ancient Councils: The Disciplinary Work of the First Four Ecumenical Councils|url=https://books.google.com/books?id=Umse6CFnt3MC|date=1996|publisher=St Vladimir's Seminary Press|location=Crestwood|isbn=978-0-88141-007-5|access-date=2014-02-24}}
* {{citation|last=Leclercq|first=Henri|title=The Catholic Encyclopedia|url=http://www.newadvent.org/cathen/10164a.htm|volume=10|access-date=19 February 2014|year=1911|publisher=Robert Appleton Company|location=New York|contribution=Meletius of Lycopolis|ref={{harvid|Leclercq|1911a}}}}
* {{citation|last=Leclercq|first=Henri|title=The Catholic Encyclopedia|url=http://www.newadvent.org/cathen/11044a.htm|volume=11|access-date=19 February 2014|year=1911|publisher=Robert Appleton Company|location=New York|contribution=The First Council of Nicaea|ref={{harvid|Leclercq|1911b}}}}
* {{citation|last=Loughlin|first=James F|title=The Sixth Nicene Canon and the Papacy|year=1880|journal=The American Catholic Quarterly Review|volume=5|pages=220–239}}
* {{citation|last=Loyn|first=Henry Royston|author-link=H. R. Loyn|title=The Middle Ages|url=https://books.google.com/books?id=6YpIPwAACAAJ|year=1991|publisher=Thames & Hudson|location=New York|isbn=978-0-500-27645-7|access-date=2014-02-24}}
* {{citation|last1=M'Clintock|first1=John |author-link1=John McClintock (theologian)|last2=Strong|first2=James|author-link2=James Strong (theologian)|title=Cyclopaedia of Biblical, Theological, and Ecclesiastical Literature|url=https://books.google.com/books?id=1uVOrP2tgG0C|volume=6|year=1890|publisher=Harper & Brothers|access-date=2014-02-24}}
* {{citation|last=MacMullen|first=Ramsay|author-link=Ramsay MacMullen|title=Voting About God in Early Church Councils|url=https://books.google.com/books?id=amKBmAEACAAJ|year=2006|publisher=Yale University Press|location=New Haven|isbn=978-0-300-11596-3|access-date=2014-02-24}}
* {{citation|title=The Canon Debate|url=https://books.google.com/books?id=5kfh68uC7ycC|year=2002|publisher=Hendrickson Publishers|location=Peabody|isbn=978-1-56563-517-3|editor-last=McDonald|editor-first=Lee Martin|editor2-last=Sanders|editor2-first=James A|ref={{harvid|McDonald & Sanders|2002}}}}
* {{citation|last=McLay|first=Denis|title=An Examination of the Role of Ossius, Bishop of Córdoba, in the Arian Controversy|journal=Ba (Hons) Dissertation – Durham University |url=https://www.academia.edu/65018532|year=2015}}
* {{citation|last=Newman|first=Albert Henry|title=A Manual of Church History|url=https://books.google.com/books?id=fjEvGE0oGVcC|volume=1|year=1899|publisher=American Baptist Publication Society|location=Philadelphia|oclc=853516|access-date=2014-02-24}}
* {{citation|last1=Newman|first1=John Henry|author-link1=John Henry Newman|last2=Williams|first2=Rowan|author-link2=Rowan Williams|title=The Arians of the Fourth Century|url=https://books.google.com/books?id=Ex7aAAAAMAAJ|date=2001|publisher=University of Notre Dame Press|location=Notre Dame|isbn=978-0-268-02012-5|access-date=2014-02-24}}
* {{citation|last=Norris|first=Richard Alfred (trans)|title=The Christological Controversy|url=https://books.google.com/books?id=9tCTomd0LcgC|series=Sources of Early Christian Thought|year=1980|publisher=Fortress Press|location=Minneapolis|isbn=978-0-8006-1411-9|access-date=2014-02-24}}
* {{citation|url=http://oca.org/saints/lives/2014/12/06/103484-st-nicholas-the-wonderworker-and-archbishop-of-myra-in-lycia|title=St Nicholas the Wonderworker and Archbishop of Myra in Lycia|access-date=22 February 2014|ref={{harvid|OCA|2014}}}}
* {{citation|author=Lutz von Padberg|title=Die Christianisierung Europas im Mittelalter|url=https://books.google.com/books?id=s0HFQAAACAAJ|year=1998|publisher=P. Reclam|isbn=978-3-15-017015-1|trans-title=The Christianization of Europe in the Middle Ages|access-date=2014-02-24}}
* {{citation|last=Rubenstein|first=Richard E|author-link=Richard E. Rubenstein|title=When Jesus became God|url=https://books.google.com/books?id=ylARAQAAIAAJ|date=1999|publisher=Harcourt Brace & Co|location=New York|isbn=978-0-15-100368-6|access-date=2014-02-24}}
* {{citation|last=Rusch|first=William G (trans)|title=The Trinitarian Controversy|url=https://books.google.com/books?id=IZ0lrSi9McYC|series=Sources of Early Christian Thought|year=1980|publisher=Fortress Press|location=Minneapolis|isbn=978-0-8006-1410-2|access-date=2014-02-24}}
* {{cite book |last1=Schaff |first1=Philip| author-link1=Philip Schaff |last2=Schaff |first2=David Schley |author-link2=David Schley Schaff |title=History of the Christian Church |url=http://www.ccel.org/ccel/schaff/hcc3 |volume=3 |year=1910 |publisher=C Scribner's Sons |location=New York }}
* {{citation|last=Tanner|first=Norman P|title=The Councils of the Church|url=https://books.google.com/books?id=grXYAAAAMAAJ|date=2001|publisher=Crossroad|location=New York|isbn=978-0-8245-1904-9|access-date=2014-02-24}}
* {{citation|last=Teres|first=Gustav|date=October 1984|title=Time Computations and Dionysius Exiguus|journal=Journal for the History of Astronomy|volume=15|issue=3|page=177|bibcode=1984JHA....15..177T|doi=10.1177/002182868401500302|s2cid=117094612}}
* {{citation|last=Vailhé|first=Siméon|title=The Catholic Encyclopedia|url=http://www.newadvent.org/cathen/15030b.htm|volume=15|year=1912|publisher=Robert Appleton Company|location=New York|contribution=Tremithus|access-date=2014-02-24}}
* {{citation |last=Vallaud |first=Dominique |title=Dictionnaire Historique |language=fr |publisher=Fayard |date=1995 |isbn=978-2-2135-9322-7}}
* {{citation|last=Ware|first=Timothy|author-link=Kallistos Ware|title=The Orthodox Church|year=1991|publisher=Penguin Adult}}
* {{citation|last=Williams|first=Rowan|author-link=Rowan Williams|title=Arius|url=https://books.google.com/books?id=C_TYAAAAMAAJ|year=1987|publisher=Darton, Logman & Todd|location=London|isbn=978-0-232-51692-0|access-date=2014-02-24}}
{{Div col end}}

==Further reading==
*{{cite journal |last1=Fernández |first1=Samuel |title=Who convened the First Council of Nicaea: Constantine or Ossius? |journal=The Journal of Theological Studies |date=2020 |volume=71 |pages=196–211 |doi=10.1093/jts/flaa036}}
*[http://www.christianitytoday.com/ch/2005/issue85/theroadtonicaea.html The Road to Nicaea] A descriptive overview of the events of the Council, by [[John Anthony McGuckin]].
*{{citation|title=Council of Nicaea|encyclopedia=Encyclopædia Britannica|date=2 January 2024 |url=https://www.britannica.com/EBchecked/topic/413817/Council-of-Nicaea}}
== External links ==
* [http://www.fourthcentury.com/index.php/nicaea-325-canons Canons of the Council of Nicaea], sponsored by [[Wisconsin Lutheran College]] and [https://www.als.org.hk Asia Lutheran Seminary].
* [https://www.fourthcentury.com/council-of-nicaea-ad-325/ Updated English Translations of the Council proceedings, Creed, Rulings (Canons), and Letters Connected to the Council], from the above site.

{{Ecumenical councils|uncollapsed}}
{{History of the Catholic Church}}
{{Catholic Church footer}}
{{Christian History}}
{{Christianity footer}}
{{Authority control}}{{portal bar|Christianity|History|Religion|Turkiye}}
{{DEFAULTSORT:Council Of Nicaea 1}}
[[Category:4th-century church councils|Nicaea 1]]
[[Category:320s in the Roman Empire]]
[[Category:First seven ecumenical councils|Nicaea 1]]
[[Category:Trinitarianism]]
[[Category:Arianism]]
[[Category:Constantine the Great and Christianity]]
[[Category:Roman Bithynia]]
[[Category:Nicaea]]
[[Category:325]]
[[Category:Date of Easter]]
[[Category:Nature of Jesus Christ]]