Christian theology

====Trinity====
{{Main|Trinity}}
[[File:Rublevtrinität ubt.gif|upright|thumb|"Holy Trinity" from the Tretyakov Gallery, Moscow, by [[Andrei Rublev]], c. 1400, but more properly known as the "Hospitality of Abraham." The three angels [[Christian symbolism|symbolize]] the Trinity.]]
For most Christians, beliefs about God are enshrined in the doctrine of [[Trinitarianism]], which holds that the three persons of God together form a single God. The Trinitarian view emphasizes that God has a will and that [[God the Son]] has two wills, divine and human, though these are never in conflict (see [[Hypostatic union]]). However, this point is disputed by Oriental Orthodox Christians, who hold that ''God the Son'' has only one will of unified divinity and humanity (see [[Miaphysitism]]).

The Christian doctrine of the Trinity teaches the unity of [[God the Father|Father]], [[God the Son|Son]], and [[Holy Spirit]] as three persons in [[monotheism|one Godhead]].<ref name="EB-purgatory">[https://www.britannica.com/eb/article-9061946/purgatory Encyclopædia Britannica: Purgatory in world religions:] {{Webarchive|url=https://web.archive.org/web/20080820181124/http://www.britannica.com/eb/article-9061946/purgatory |date=20 August 2008 }} "The idea of purification or temporary punishment after death has ancient roots and is well-attested in early Christian literature. The conception of purgatory as a geographically situated place is largely the achievement of medieval Christian piety and imagination."</ref> The doctrine states that [[God]] is the Triune God, existing as three ''persons'', or in the [[Koine Greek|Greek]] ''[[hypostasis (religion)|hypostases]]'',<ref>See discussion in {{CathEncy|wstitle=Person}}</ref> but one being.<ref>Grudem, Wayne A. 1994. ''Systematic Theology: An Introduction to Biblical Doctrine.'' Leicester, England: Inter-Varsity Press; Grand Rapids, MI: [[Zondervan]]. p. 226.</ref> Personhood in the Trinity does not match the common Western understanding of "person" as used in the English language—it does not imply an "individual, self-actualized center of free will and conscious activity."<ref name=Olsen>{{cite book |last=Olson |first=Roger E. |title=The Story of Christian Theology: Twenty Centuries of Tradition & Reform. |publisher=InterVarsity Press |year=1999 |isbn=978-0-8308-1505-0 |url=https://archive.org/details/storyofchristian00olso }}</ref>{{rp|185–186.}} To the ancients, personhood "was in some sense individual, but always in community as well."<ref name=Olsen/>{{rp|p.186}} Each ''person'' is understood as having the one identical essence or nature, not merely similar natures. Since the beginning of the [[Christianity in the 3rd century|3rd century]]<ref>{{Cite web|url=http://www.ccel.org/ccel/schaff/anf03.v.ix.ii.html |title=Tertullian, Against Praxeas, chapter II |publisher=Ccel.org |date=1 June 2005 |access-date=2010-08-08}}</ref> the doctrine of the Trinity has been stated as "the one God exists in three Persons and [[homoousios|one substance]], Father, Son, and Holy Spirit."<ref name="ODCC-Doctrine" />

Trinitarianism, belief in the Trinity, is a mark of [[Roman Catholic Church|Catholicism]], [[Eastern Orthodox Church|Eastern]] and [[Oriental Orthodoxy]] as well as other prominent Christian sects arising from the [[Protestant Reformation]], such as [[Anglicanism]], [[Methodism]], [[Lutheranism]], [[Baptist]], and [[Presbyterianism]]. ''The Oxford Dictionary of the Christian Church'' describes the Trinity as "the central dogma of Christian theology".<ref name="ODCC-Doctrine">{{cite encyclopedia |encyclopedia=he Oxford Dictionary of the Christian Church |publisher=Oxford University Press |year=2005 |isbn=978-0-19-280290-3 |title=Trinity, doctrine of the}}</ref> This doctrine contrasts with [[Nontrinitarian]] positions which include [[Unitarianism]], [[Oneness Pentecostalism (doctrine)|Oneness]] and [[Modalism]]. A small minority of Christians hold non-trinitarian views, largely coming under the heading of [[Unitarianism]].

Most, if not all, Christians believe that God is spirit,<ref>{{bibleverse|John|4:24}}</ref> an uncreated, [[Omnipotence|omnipotent]], and eternal being, the creator and sustainer of all things, who works the redemption of the world through his Son, Jesus Christ. With this background, belief in the [[Christology|divinity of Christ]] and the Holy Spirit is expressed as the doctrine of the [[Trinity]],<ref>J.N.D. Kelly, ''Early Christian Doctrines'' pp. 87–90; T. Desmond Alexander, ''New Dictionary of Biblical Theology'' pp. 514–515; Alister E. McGrath, ''Historical Theology'' p. 61.</ref> which describes the single divine ''[[ousia]]'' (substance) existing as three distinct and inseparable ''hypostases'' (persons): the [[God the Father|Father]], the Son ([[Jesus|Jesus Christ]] the [[Logos (Christianity)|Logos]]), and the [[Holy Spirit]].<ref>{{bibleverse|1John|5:7||1 Jn 5:7 }}</ref>

The Trinitarian doctrine is considered by most Christians to be a core tenet of their faith. [[Nontrinitarians]] typically hold that God, the Father, is supreme; that Jesus, although still divine Lord and Savior, is the [[Son of God]]; and that the Holy Spirit is a phenomenon akin to God's will on Earth. The holy three are separate, yet the Son and the Holy Spirit are still seen as originating from God the Father.

The [[New Testament]] does not have the term "Trinity" and nowhere discusses the Trinity as such. Some emphasize, however, that the New Testament does repeatedly speak of the Father, the Son, and the Holy Spirit to "compel a trinitarian understanding of God."<ref name=Stagg-p38>{{cite book |last=Stagg |first=Frank |title=New Testament Theology |publisher=Broadman Press |year=1962 |isbn=978-0-8054-1613-8 |page=[https://archive.org/details/newtestamenttheo0000stag/page/38 38 ff] |url=https://archive.org/details/newtestamenttheo0000stag/page/38 }}</ref> The doctrine developed from the biblical language used in New Testament passages such as the baptismal formula in {{bibleverse|Matthew|28:19}} and by the end of the [[Christianity in the 4th century|4th century]] it was widely held in its present form.