Jude 1:5 - Joseph Benson’s Commentary on the Old and New Testaments

I will therefore put you in remembrance, &c. I will remind you of some examples of God's judgments against such persons. Œcumenius observes, that “by proposing the following examples of the destruction of sinners from the Old Testament history, the apostle designed to show, that the God of the Old Testament is the same with the God of the New, in opposition to the Manicheans, who denied this; also to prove that the goodness of God will not hinder him from punishing the wicked under the new dispensation, any more than it hindered him from punishing them under the old.” In this passage Jude has mentioned two of the instances of the divine vengeance against atrocious sinners, which Peter took notice of, 2 Peter 2:4-5, (where see the notes,) and in place of the third instance, the destruction of the old world, he hath introduced the destruction of the rebellious Israelites in the wilderness. Though ye once knew this Were informed of it, and received it as a truth; that the Lord, having saved the people out of Egypt By a train of wonderful miracles; afterward destroyed them that believed not That is, destroyed the far greater part of that very people, whom he had once saved in a very extraordinary manner. Let no one, therefore, presume upon past mercies, as if he were now out of danger. Jude does not mention the various sins committed by the Israelites in the wilderness, such as their worshipping the golden calf, refusing to go into Canaan, when commanded of God, their fornication with the Midianitish women, their frequent murmurings, &c., but he sums up the whole in their unbelief, because it was the source of all their sins.