The letter of Jude, or more accurately, Judah, according to the pronunciation of his name both in Greek and in Hebrew.
Jude was one of Jesus' four brothers who are named in the Gospel accounts. James, Joses, Simon, and Jude.
None of the brothers followed Jesus as the Messiah before his death but after his resurrections they saw him alive and then became his disciples. All these brothers of Jesus became leaders eventually in the first Jewish Christian communities. And Jude was known as a traveling teacher and missionary. And this gives us the background to understand the purpose of his letter.
We don't know what specific church community he wrote to, but it was likely made up of mostly Messianic Jews. His writing style assumes a deep knowledge of the Old Testament Scriptures as well as other popular Jewish writings.
Jude had become aware of a crisis facing the church he was writing to and so this helps us understand the letter's intent.
It begins with an opening charge followed by a long warning and accusation against corrupt teachers who had influenced this church.
And then Jude closes by completing the charge about what this church is supposed to do.
Jude begins by charging this church to contend for the true Christian faith. He says his plan was to write a longer work that explored our shared salvation through the Messiah, but that got delayed when he heard the urgent news about this church and so he sends his very thoughtful but very short letter.
Jude doesn't begin with how they're supposed to contend for the faith, but rather why.
He says it's because of the corrupt teachers who have infiltrated this church. It's not their teaching that he points to but their way of life. Their moral compromises.
First, they've distorted God's grace as a license to sin. They think that they're forgiven and they have God's Spirit, so now they can do whatever they want like sexual immorality, rejecting authority, and speaking evil of important people.
Jude is saying that these false teachers pervert the words of scripture for their own immoral desires.
Peter says a similar thing in 2 Peter 2:1 "But there were also false prophets among the people, even as there will be false teachers among you, who will secretly bring in destructive heresies, even denying the Lord who bought them, and bring on themselves swift destruction."
Peter also describes the issues with these teachers by saying “And many will follow their destructive ways, because of whom the way of truth will be blasphemed. By covetousness they will exploit you with deceptive words; for a long time their judgment has not been idle, and their destruction does not slumber. 2 Peter 2:2-3
Jude first offers three Old Testament warnings against backsliding.
The first example is the Israelites who God brought out of Egypt. The ones who did not believe died in the wilderness.
Then he mentions the fallen angels who sinned. They were once holy in heaven then backslid into sin and were cast to the earth, then will be held in chains for judgment with Satan during the thousand years and then destroyed in the lake of fire.
The third case of back sliding is Sodom and Gomorrah and the cities near them. Jude says they had given themselves over to sexual immorality and gone after strange flesh. He says they are an example to the church. They suffered the vengeance of eternal fire because of their wickedness.
Jude compares what the people in Sodom and Gomorrah were doing, to what these false teachers were doing. They both commit sexual immorality in going after both men and women which Jude calls strange flesh.
He then calls these false teachers "Dreamers" and added to their list of sins which are rejecting authority and speaking evil of dignitaries which God specially forbids in Exodus 22:28 which says “You shall not revile God, nor curse a ruler of your people.” Peter says there are those who despise authority or speak evil of dignitaries. The reason that Peter gives for them doing this, is because they are presumptuous and self-willed. Jude says they speak evil of whatever they do not know. In contract, God's way is to be humble and to follow God's will and let Him setup and take down those in authority.
Both Jude and Peter say that the angels, who are greater in power and might, do not bring a reviling accusation against authorities before the Lord.
Jude then says these false teachers are like three others in the old testament; Cain, Balaam, and Korah.
The reason for being like Cain is not given by Jude but John says that Cain's works were evil. Presumably referring to Cain's wrong sacrifice. These teachers were also doing evil things.
