3, 4. When I gave all diligence. His thought was that when he proposed to write diligently and carefully some need impelled him to write at once, more briefly perhaps than he had purposed. Earnestly contend for the faith which was once, etc. He exhorts to contend for the faith delivered once for all, the faith without innovation, the gospel of the apostles in distinction from the adulterations of false teachers. The doctrine of a progressive revelation after the apostles is not found in the New Testament. 4. For there are certain men. Men who have crept in without their character being understood. Who were before of old ordained to this condemnation. Whose coming was predicted and whose lives were placed under condemnation. See verse 14 and also verse 17. To this condemnation. This condemnation which comes on all the ungodly. Turning the grace of our God. Of the gospel. Instead of self-restraint they live lascivious lives. The warrant for this was found in "the freedom of the children of God." From the very times of the apostles there have been Antinomians who have held that what was sin to others might be permitted to the sanctified. They asserted that the Spirit was not defiled by the sins of the body. Denying our only Lord Jesus Christ. "Lord God" is not found in the best manuscript. Their denial of Christ was a denial that he had come in the flesh. These sectaries held that the flesh was wholly sinful.
5-7. I will therefore put you in remembrance. Of how God speaks judgments on sinners. How that the Lord, etc. Having saved the people out of Egypt, the people were destroyed for their sins in the wilderness. See Num. 14:29. 6. And the angels which kept not their first estate. See note on 2 Pet. 2:4. These angels, then, had fallen. Created holy, they had sinned and become wicked angels, or evil spirits. Left their own habitation. Their own proper home. Some see a reference to Gen. 6:2. He hath reserved. God hath imprisoned them and kept them for judgment. 7. Even as Sodom and Gomorrha. See notes on 2 Pet. 2:6, 10; also Gen. 19:24. For their lasciviousness terrible destruction came upon them. Set forth for an example. Utterly destroyed by fire they are an example that points to the eternal fire.
8-10. Likewise also these filthy dreamers. These men who are agitated by impure dreams. Despise dominion. See notes on 2 Pet. 2:10. 9. Yet Michael the archangel. Michael is brought forward as a contrast with those who speak evil of dignities. He is called by Daniel "the Great Prince," and here the archangel, or head angel. Yet in addressing the devil, a fallen angel, he did not rail at him, but only said, "The Lord rebuke thee." The reference is not to a statement of the Bible, but to a Jewish tradition which held that the burial place of Moses was placed under the charge of Michael. 10. But these speak evil of those things which they know not. Of spiritual and unseen things. But what they know naturally. By the natural senses. In these things they corrupt themselves.
11-13. Woe unto them! The denunciation of woes, common in the Lord's ministry, is only found here in all the rest of the New Testament. Gone in the way of Cain. Living selfish lives, full of hate. After the error of Balaam. Like Balaam trying to make a gain of godliness. See notes on 2 Pet. 2:15. Perished in the gainsaying of Core. Like Balaam they are false prophets. Like Korah, who profanely thrust himself into the priesthood and perished, they intrude irreverently into holy places. 12. These are spots in your feasts of charity. See notes on 2 Pet. 2:13. They engaged in revelings at the Agape, the love feasts. Clouds they are without water. Rainless clouds. See notes on 2 Pet. 2:17. Trees . . . without fruit. Fruitless, barren. Twice dead. Doubly dead, hence, no hope of fruit. 13. Raging waves of the sea. Roaring and foaming like the sea waves. Wandering stars. Stars not fixed in their places, but shooting like meteors, and then going out. "Shooting stars" is not far from the idea. To whom is reserved, etc. As the shooting stars go out in darkness, so these will pass into eternal darkness.
14, 15. And Enoch also. This prophecy of the holiest man of the antediluvian world might have been preserved by tradition. It is found in the Book of Enoch, a work long lost, but recovered in modern times in Abyssinia, supposed to have been composed the century before Christ. Wherever Jude met it, he was familiar with the prophecy. The seventh from Adam. To the Jew there was a sacredness in seven. Prophesied of these. These blasphemers. The prophecy is quoted. 15. To execute judgment upon all. For a general judgment. To convince. To convict all ungodly men of their ungodly deeds.
16-19. These are murmurers. They murmur at God's providence and complain of his laws. Having men's persons in admiration. Being respecters of persons for the sake of self-interest. 17. Remember ye the words . . . spoken before of the apostles. The language implies that Jude was not an apostle. 18. How that they told you there would be mockers. See 2 Pet. 3:3; 1 Tim. 4:1; 2 Tim. 3:1. Last time. In the last dispensation. 19. These be they. Already this is being fulfilled. Who separate. Who separate themselves from God and the communion of saints. Sensual. Living an animal rather than a spiritual life.
20-23. Building up yourselves. Instead of separating from the faith. Praying in the Holy Spirit. See notes on Eph. 6:18. 21. Keep yourselves in the love of God. By holy lives and  prayer. 22. On some have mercy, who are in doubt. See the Revision. The thought is to be very gentle and pitiful to those disturbed by doubt. 23. And some save, snatching them out of the fire. By snatching away from sin by the most vigorous effort. By stern preaching. Some have mercy with fear. Mercifully point out the danger. Hating even the garment, etc. All the while abhorring their sins.
24, 25. Now unto him. God. Who is able. To work out our full salvation. Before the presence of his glory. In his glorious presence. 25. The only God our Savior. Our Savior "through Jesus Christ." Be glory. Not only glory forever and ever, but eternal and universal dominion.