James C. VanderKam writes of 1 Enoch 93:1-10 and 91:11-17 “The oldest surviving historical apocalypse in Jewish literature is probably the short composition known as the Apocalypse of Weeks. The fact that it does not mention the persecution of Jews and the ban on Judaism by Antiochus IV in 167 BCE implies that it was written before these events, that is, perhaps in approximately 170 BCE.
It has accidentally been divided into two parts in the Ethiopian version of 1 Enoch and the order of the two parts reversed; an Aramaic manuscript from Qumran preserves much of the apocalypse and has the parts in the correct order (4Q212). The apocalypse takes the form of Enoch’s report to Methuselah regarding a vision he had seen; the text also mentions words of the angels and the contents of the heavenly tablets as the sources of the revelation disclosed to him.
In the report he quickly sketches history from beginning to end, with almost all of it packaged as a prediction. History and the different stages of the judgment are divided into ten units called ‘weeks.’
These seven-part units are suggestive for several reasons: they are one of a number of references and allusions to ‘sevens’ in the apocalypse (e.g., Enoch is the seventh patriarch); the ten ‘weeks’ total seventy units, itself a highly significant number in light of Jeremiah’s prediction that Jerusalem would be desolate for the seventy years of Babylonian control (see Jer. 25:11-12; 29:10; Dan. 9:2, 24-27); and the decisive ‘week,’ that is, the one in which the actual author lives and when the great turning point in history will begin is the seventh. As 7 x 7 = 49, the total brings to mind associations with the biblical jubilee (which the author of Jubilees and others understood as a forty-nine-year unit).”