Babylonian Calendar - Days

Days

Counting from the new moon, the Babylonians celebrated every seventh day as a "holy-day", also called an "evil day" (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, apparently at nightfall to avoid the prohibitions: Merodach and Ishtar on the 7th, Ninlil and Nergal on the 14th, Sin and Shamash on the 21st, and Enki and Mah on the 28th. Tablets from the sixth-century BC reigns of Cyrus the Great and Cambyses indicate these dates were sometimes approximate. The lunation of 29 or 30 days basically contained three seven-day weeks, and a final week of eight or nine days inclusive, breaking the continuous seven-day cycle.

Among other theories of Shabbat origin, the Universal Jewish Encyclopedia advanced a theory of Assyriologists like Friedrich Delitzsch that Shabbat originally arose from the lunar cycle, containing four weeks ending in Sabbath, plus one or two additional unreckoned days per month. The difficulties of this theory 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. According to Marcello Craveri: "The Sabbath (in Hebrew Shabbath) was almost certainly derived from the Babylonian Shabattu, the festival of the full moon, but, all trace of any such origin having been lost, the Hebrews ascribed it to Biblical legend."

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". Sacrifices were offered to Ninurta and the day dedicated to Gula, and it may be supposed that prohibitions were strengthened.

Further, reconstruction of a broken tablet seems to define the rarely attested Sapattum or Sabattum as the 15th day of the lunation, more or less the full moon. This word is cognate with Hebrew Shabbat, but is monthly rather than weekly; it is regarded as a form of Sumerian sa-bat ("mid-rest"), attested in Akkadian as um nuh libbi ("day of mid-repose"). This conclusion is a contextual restoration of the damaged Enûma Eliš creation account, which reads: "bbath shalt thou then encounter, midly."