As Jude uses Old Testament realities to remind the church of the inevitable end of false teaching, whether bondage or wrath, he exposes how these teachers crept in. Forgetfulness of the gospel provides a way for false teaching to creep into our midst. In the end, it is better to pay the price of remembering than to pay the price of forgetting.
Now I want to remind you, although you once fully knew it, that Jesus, who saved a people out of the land of Egypt, afterward destroyed those who did not believe. And the angels who did not stay within their own position of authority, but left their proper dwelling, he has kept in eternal chains under gloomy darkness until the judgment of the great day— just as Sodom and Gomorrah and the surrounding cities, which likewise indulged in sexual immorality and pursued unnatural desire, serve as an example by undergoing a punishment of eternal fire.
And the Lord said to Moses, “How long will this people despise me? And how long will they not believe in me, in spite of all the signs that I have done among them? I will strike them with the pestilence and disinherit them, and I will make of you a nation greater and mightier than they.”
And as soon as he had finished speaking all these words, the ground under them split apart. And the earth opened its mouth and swallowed them up, with their households and all the people who belonged to Korah and all their goods. So they and all that belonged to them went down alive into Sheol, and the earth closed over them, and they perished from the midst of the assembly. And all Israel who were around them fled at their cry, for they said, “Lest the earth swallow us up!” And fire came out from the Lord and consumed the 250 men offering the incense.
But you must remember, beloved, the predictions of the apostles of our Lord Jesus Christ.