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Yet Michael the archangel, when contending with the devil he disputed about the body of Moses, durst not bring against him a railing accusation, but said, The Lord rebuke thee. — Jude 9
This event is not spoken of anywhere else in the Bible, as is commonly known. Some early Christian theologians said that this story came from The Assumption of Moses, although that part does not appear in the manuscripts that we have today.
An alternative explanation is that Jude is compounding material from three sources:
General Jewish traditions about Michael as gravedigger for the just as in the Apocalypse of Moses
Contrast with the accusation by Michael of Azazel in the Book of
Contrast with the angel of the Lord not rebuking Satan over the body of Joshua the High Priest in Zechariah 3.
This explanation has in its favour three arguments: (1) Jude quotes from both 1 Enoch 1:9 and Zechariah 3. (2) Jeshua in Zechariah 3 is dead - his grandson is serving as high priest. The change from "body of Jesus" (Greek spelling of Jeshua) to "body of Moses" would be required to avoid confusion with Jesus, and also to reflect the historical context of Zech. 3 in Nehemiah concerning intermarriage and corruption in the "body" of the priesthood. (3) The example of Zech. 3 provides an argument against the "slandering of heavenly beings", since the Angel of the Lord does not do in Zech. 3 what Michael is reported to do in 1En1.
One would also, in this interpretation, need to explain how "the angel of the LORD", who is clearly God Himself in Zechariah 3, became Michael the archangel.
Does Jude affirm that this event happened, or does he reference a well-known tradition to make a theological point, without necessarily affirming that it is historical? Is there any evidence in the text to support either position?