Sabbath

===Babylonian rest days===
{{Main article|Babylonian calendar#Days|Shappatum}}
{{unreferenced section|date=December 2022}}
Counting from the [[new moon]], the Babylonians celebrated the 7th, 14th, 21st, and 28th as "holy-days", also called "evil days" (meaning "unsuitable" for prohibited activities). On these days officials were prohibited from various activities and common men were forbidden to "make a wish", and at least the 28th was known as a "rest-day". On each of them, offerings were made to a different god and goddess. Tablets from the 6th-century BCE reigns of [[Cyrus the Great]] and [[Cambyses II|Cambyses]] indicate these dates were sometimes approximate. The [[lunation]] of 29 or 30 days basically contained three [[seven-day week]]s, and a final week of nine or ten days inclusive, breaking the continuous seven-day cycle. The Babylonians additionally celebrated the 19th as a special "evil day", the "day of anger", because it was roughly the 49th day of the (preceding) month, completing a "week of weeks", also with sacrifices and prohibitions.<ref>{{cite book|author=Pinches, T.G.|editor=Hastings, James|others=Selbie, John A., contrib|title=Encyclopedia of Religion and Ethics|publisher=Charles Scribner's Sons|year=1919|pages=889–891|chapter=Sabbath (Babylonian)|chapter-url=https://archive.org/details/encyclopaediaofr10hast_0/page/888/mode/2up}}</ref> Difficulties with [[Friedrich Delitzsch]]'s [[origin theory]] connecting Hebrew ''[[Shabbat]]'' with the Babylonian [[lunar cycle]] include reconciling the differences between an unbroken week and a lunar week, and explaining the absence of texts naming the lunar week as ''Shabbat'' in any language. Reconstruction of a broken tablet seems to define the rarely attested Babylonian [[Akkadian Empire|Akkadian]] word ''Sapattu<sup>m</sup>'' or ''Sabattu<sup>m</sup>'' as the [[full moon]]: this word is cognate or merged with Hebrew ''Shabbat'', but is monthly rather than weekly. It is regarded as a form of [[Sumer]]ian ''sa-bat'' ("mid-rest"), attested in [[Akkadian language|Akkadian]] as ''um nuh libbi'' ("day of mid-repose"). This conclusion is a contextual restoration of the damaged [[Enûma Eliš]] [[creation mythos]], which is read as: "[Sa]pattu shalt thou then encounter, mid[month]ly."

The [[pentecontad calendar]], thought to be of [[Amorite]] origin, includes a period known to [[Babylonia]]ns as ''Shappatum''. The year is broken down into seven periods of fifty days (made up of seven weeks of seven days, containing seven weekly Sabbaths, and an extra fiftieth day, known as the ''atzeret''), plus an annual supplement of fifteen or sixteen days, called ''Shappatum'', the period of harvest time at the end of each year. Identified and reconstructed by Hildegaard and Julius Lewy in the 1940s, the calendar's use dates back to at least the 3rd millennium BCE in Western [[Mesopotamia]] and surrounding areas; it was used by the [[Canaan]]ite tribes, thought by some to have been used by the [[Israelite]]s prior to [[King Solomon]], and related to the [[liturgical]] calendar of the [[Essene]]s at [[Qumran]]. Used well into the modern age, forms of it have been found in [[Nestorianism]] and among the [[Palestinian people|Palestinian]] ''[[fellaheen]]''. Julius Morgenstern believed that the calendar of the [[Jubilees]] had ancient origins as a somewhat modified survival of the pentecontad calendar.