Comments by "EebstertheGreat" (@EebstertheGreat) on "ReligionForBreakfast" channel.

The Enoch calendar is 364 days long, which is why he is said to have lived 365 years. This day-year conversion is seen multiple times in the Bible. The calendar has four seasons of 13 weeks each; moreover, each season is divided into three months, with the first two 30 days long and the third 31 days long. It's a very convenient calendar and uses the fact that 364 is a multiple of 28. However, it would drift rather quickly and require some sort of intercalation, which seems to be precluded by the 8-year cycle described in the book. Most solar calendars at the time did use intercalation, though some were 365 days long and just drifted by about 6 hours a year.
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0:23 In Latin, "Jupiter" was typically spelled "Iuppiter," with a doubled p instead of a macron over the u. It's the same thing that happened to "littera." The "Iūpiter" variant is presumably older, but you don't see it very often in ancient texts and almost never in Medieval texts.
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