Perhaps one of the strangest statements in the New Testament is found in Jude 9:
"But Michael the archangel, when he disputed with the devil and argued about the body of Moses, did not dare pronounce against him a railing judgment, but said, “The Lord rebuke you!”"
This statement has been recognized as coming from the account, "The Assumption of Moses" through identification of the Church Fathers however the ending to the only version we have today has been lost and so does not include this part of the account. It is believed that our modern "Assumption of Moses" was created through the merging of two different books containing related tradition.
As far as the quote in Jude goes, Michael's rebuke to Satan is identical to what we find in Zechariah 3:2,
“The Lord said to Satan, “The Lord rebuke you, Satan! Indeed, the Lord who has chosen Jerusalem rebuke you! Is this not a brand plucked from the fire?”” (Zechariah 3:2 0
The term "brand plucked from the fire" finds its parallel in Jude 23's "snatching them out of the fire" which also includes reference to a "polluted garment" alluding again back to Zechariah 3, this time verse 3.
The parallel between these two passages (Jude and Zechariah) has caused some to see Jude directly citing this incident and thus identifying Michael the Archangel as "the Angel of the Lord". However, Jude's reference to "the body of Moses" remains unexplained. Some have suggested this as a term for the priesthood to fit Zechariah's context, but no known use of "the body of Moses" in reference to the priesthood exists. Why then do such similarities exist between these two passages?
The only work I could find that seeks to search out a connection between these two passages is helpful here (https://journals.sagepub.com/doi/pdf/10.1177/0142064X17740003). Here, the author demonstrates that Zechariah 3 was often used in Jewish and early Christian literature in the contexts of ascension stories involving demonic or simply angelic opposition. This can be seen in "The Apocalypse of Abraham" and "The Ascension of Isaiah". While the author is helpful here, his conclusion ultimately must be rejected, as he concludes that the most likely scenario for what Jude is referring to is a story in which Moses did not die, but was opposed by Satan on the basis that Moses lacked a glorified body and thus wasn't fit to enter Heaven. This runs contrary to the clear statement of Deuteronomy 34:5-6 that Moses died and was buried.
So where do we go from here? It would seem that we either have a problem since intertextual evidence seems to indicate "The Assumption of Moses", which Jude quotes, involves Moses being taken into Heaven or there is some solution to this issue, but since we lack the ending of the text, we're left to endless speculation.
I would suggest that this isn't so. While no actual copy of "The Assumption of Moses" exists today with the ending, the ending itself does appear in Origen's "On the Freedom of the Will". This allows us to put the pieces of evidence we have together, and I believe that when we do so, a clear picture emerges as to what actually happened at Moses' death.
Origen's ending informs us that we are in fact dealing with an ascent story in "The Assumption of Moses", and that Moses' body does play a key role here; however, this isn't a story about Moses' body ascending.
According to Origen's ending, Michael the Archangel was appointed to bury Moses' body. Satan opposed Michael on the basis that Moses' body should belong to him and that Moses was a murderer because he killed an Egyptian. Michael rebukes Satan (or rather, says "The Lord rebuke you!") and says that Satan was behind the serpent in the Garden of Eden. With satanic opposition removed, Moses' assumption takes place, however, this is an assumption of Moses' soul, which is seen by Joshua and Caleb to be carried into the Heavens with angels, while Moses' body remains on Earth, where it is later buried by the Archangel. Not only does this reconcile the evidence we have about "The Assumption of Moses" being an ascension story with the end of Deuteronomy, but it also appears that Targum Jonathan even assumes this tradition.
One implication we can reach based off this conclusion, is that the reason that Jude alludes to Zechariah is because in a sense Zechariah is actually alluding to Jude in the first place. In other words, given the truth about this story of Moses' death, Zechariah would have known about this back in his time, and thus wrote Zechariah 3 with this tradition already in mind. This is why early Jewish and Christian literature use Zechariah 3 in reference to stories with themes of ascension and demonic opposition in the first place: Zechariah was already thinking intertextually (if I can use that word to refer to a previous unwritten tradition) when he wrote his 3rd chapter.
