It is acknowledged that Judaism of the Second Temple period (i.e. up to 70CE) consisted of several groups all vying for precedence in regard to religious/cultural/political ideology. There is a body of evidence and scholarship suggesting that one such movement favoured the patriarch Enoch as revelator (in precedence, particularly, over Moses). The so-called 'Enoch literature' promotes a solar 364 day calendar as a major part of its revision, with Jubilees tying this in to the preordained harmonic structure of the cosmos which has since become corrupt. The group behind these texts, who appear to have some relationship to the Qumran sect, seem to have believed that only by following the divine solar calendar could festivals and sabbaths be accurately timed so as to concur with the heavenly ordinations; merely observing the movements of the planets would lead to error as the material world had fallen from grace. This Enochic tradition thus pulled away from much of the orthodoxy of the Temple practice, feeding into alternative currents such as Essenism, Qumran and, eventually, Christianity (the Enoch literature in particular was much used by the early Church, and much of their mystical/speculative/revisionist/anti-law thought also fell on glad ears with early Christians, many of whom were Jewish). After the destruction of the Second Temple in 70CE and the emergence of Christianity as a religion in its own right, the Rabbis (emerging from the Pharisees) began restructuring the faith, emphasising what they believed were the correct and original principles. This included a definite movement away from the heterodox and apocalyptic ideas which had caused so much strife in recent history: the Enochic being one example. Due to the lack of central Temple, the faith had to find a new central focus which became the , i.e. the Mosaic law. Clearly the challenge presented by Enoch could have little place in this.
As regards heavenly ascension/Merkavah Mysticism, Alan Segal in his book 'Two Powers In Heaven' makes a good case for this tradition also relating to the ascension of patriarchs and prophets (including Enoch, Jacob, Moses et al), something which the rabbinic normalisers saw as particularly dangerous for general consumption, although not ineffective in the correct hands.
Hopefully this provides an adequate summary. There is much current scholarship on the Enochic tradition: Andrei Orlov's 2004 book 'The Enoch-Metatron Tradition' is very good (but very expensive); in relation to the calendar, David Jackson's 'Enochic Judaism: Three Defining Paradigm Exemplars' provides much interesting information.
- Shemikhazah, the Watcher (fallen angel) who led his followers into sexual liaison with human women, siring a race of Giants. This is an example of deviation from the separation of human-angelic.
- Aza'el, the Watcher who taught humans technologies of war and beautification which brought great suffering and wickedness; this is breaking the rules by bringing heavenly secrets to earth, and humans going astray from what is good and proper.
- Finally, the cosmos falling out of sync with the divine plan due to the disobedience/laxity of the spirits responsible for the movement of stars and planets. This is calendrical deviation.
So, all three examples relate to straying from the prescribed divine course. As such, jackson Israel to the true course, i.e. back to proper observation of the divine commandments and away from hellenism. It has often been noted that there is an overarching emphasis in the Enoch literature on regularity: it presents a minutely ordered, clockwork universe where any deviation is seen as sinful. The 364 day calendar is understood to be so perfect that it must be the way God ordered the universe; the irregularity of either the lunar, or even a 365.25 day calendar can only be the result of the natural world going astray from God's plan. Of course, this all relates very clearly to the transmission of this knowledge in these writings, from the most righteous patriarch Enoch, from before the destruction of the flood. Jackson of course goes into the specifics in very great detail which I won't recount here...the book's available on Amazon and not too pricey, though I'd warn anyone considering it that it is written by an academic for academics and I don't doubt that it would be almost impenetrable to anyone not already aware of the fundamentals of the Enochic literature (he provides zero background).