Jude 1:9 refers to an event found nowhere else in the Bible, stating: "But when the archangel Michael, contending with the devil, was disputing about the body of Moses, he did not presume to pronounce a blasphemous judgment, but said, 'The Lord rebuke you.'" Why were Michael and Satan disputing about the body of Moses?
Why did Michael and Satan dispute over the body of Moses in Jude 1:9?
No specific reason is given, but several theories have been suggested. One could be that people have a propensity to worship the created things (to include creation), rather than our Creator. Romans 1:25 says people "exchanged the truth about God for a lie and worshiped and served the creature rather than the Creator." An example of this happening in the Old Testament is when the Israelite people worshipped the bronze serpent that Moses had made (per God's instructions, but intended as a symbol not as an idol to be worshiped; see Numbers 21:4–9 and John 3:12–16), rather than God (2 Kings 18:3–4). One of the greatest difficulties that Jesus had with the Pharisees, was their worship of the Law of Moses, rather than letting the Law lead them to their need for a Savior. Perhaps Satan wanted the body of Moses to be available to the people to tempt them into worshipping Moses' bones rather than God.
Another theory is that Satan, the accuser (Revelation 12:10), was resisting Moses being raised to eternal life because of his prior sins, specifically the one at Meribah that prevented him from entering into the Promised Land (Deuteronomy 32:48–52) or his killing of the Egyptian in Exodus 2.
In regards to additional historical information about this passage, it is thought that Jude may have referred to an extra-biblical account known in the first century as the Assumption of Moses. Though lost today, the church leader Origen mentioned this account in the third century (another document also called the Assumption of Moses exists and may or may not be related to the one Origen mentions). The account apparently included a description of Michael and Satan disputing over the body of Moses which would fit the context of Jude 1:9.
This does not necessarily mean this lost Assumption of Moses is an inspired book, but rather that it was a story known to Jude's readers. It appears Jude, writing with the inspiration of the Holy Spirit (2 Peter 1:20–21), confirmed this particular account was true. He used it as an illustration of the respect the angel Michael had, in contrast with the disrespect of the false teachers whose pride led them to much sin. As a side note, this is instructive to us in terms of our dealings with Satan and demons. Rather than try to stand against them in our own authority, we are to seek the Lord's power against them. We call out to Him to intervene and trust in His power and authority.
This illustration of Michael and Satan is one in a list given by Jude in verses 9–11. In addition to the example of Michael and the devil, Jude notes the example of Cain (who murdered his brother Abel in Genesis 4), Balaam's error (Numbers 31), and Korah's rebellion (Numbers 16). All four of these examples refer to historical events from the time of the Pentateuch (Genesis to Deuteronomy). Jude appeared to refer to events from this part of the Bible, known as the Torah, as a strong authority for his claims.
Interestingly, these four examples follow three previous examples also connected with the Torah. Verses 5–7 mention the people God rescued from Egypt who were later judged for unbelief, angels who rebelled against God (likely referring to Genesis 6:1–4), and the judgment of Sodom and Gomorrah (Genesis 18—19).
These examples clearly note Jude's emphasis on the Torah (God's previous revelation) as well as his likely Jewish audience for the letter. He referred to well-known events in Jewish history that included Scripture as well as extra-biblical material (such as Enoch in Jude 1:14 that appears to refer to the book of 1 Enoch). These connecting points served as ways for Jude to provide examples for his teaching against false teachers, highlighting the true teachings of Jesus Christ that His followers were expected to follow. They were to avoid unhealthy teaching (Titus 1:9), knowing that such beliefs led to sin and were displeasing to the Lord.
The basic principle of Jude is to ensure our hearts and lives are submitted completely to God, and that we worship Him in our words, thoughts, and actions. In other words, we put aside the "I want to do what I want to do when I want to do it" mentality and choose to follow God instead. Jude writes, "But you, beloved, building yourselves up in your most holy faith and praying in the Holy Spirit, keep yourselves in the love of God, waiting for the mercy of our Lord Jesus Christ that leads to eternal life" (Jude 1:20–21).
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Who is Satan?
Truth about Angels