Jude 1:9

Jude 1:9. They do against dignities what even the archangel would not do against Satan. Michael (‘who is like God') was regarded as the guardian angel of the nation of Israel (Daniel 12:1; cp. Daniel 10:13; Daniel 10:21). In the New Testament he is mentioned only here and in Revelation 12:7. ‘Archangel' is mentioned only here and in 1 Thessalonians 4:16.

about the body of Moses. The Jews had various traditions about the burial of Moses. According to Jonathan (on Deuteronomy 34:6), the grave of Moses was given to the special care of Michael; and to this tradition most commentators ascribe the introduction of the circumstance here. Others suppose that Christ Himself, in connection with the appearance of Moses at the Transfiguration, may have sanctioned the tradition. Nothing is said of it in the Book of Enoch.... Origen speaks of a book extant in his day (the Assumption or Removal of Moses) as the source whence Jude derived his account; but there is no evidence that the book was in existence when Jude wrote. The most probable explanation is that there was a Jewish tradition to which Jude appeals.

when contending he disputed shows that it was verbal altercation not unlike that recorded in the case of Job (chap. 1) and in Zechariah 3:1-3. The solution that God revealed these facts to Jude is of course possible, but it is not likely. That the facts should be previously known is of the very essence of the argument.