The little letter of Jude teaches us something about the value of learning history. This is not the main point of the letter. But it is striking. In this next-to-last book of the Bible, Jude writes to encourage the saints to "contend earnestly for the faith which was once for all handed down to the saints" (Jude 1:3).
The letter is a call to vigilance in view of "certain persons [who] have crept in unnoticed . . . ungodly persons who turn the grace of our God into licentiousness and deny our only Master and Lord, Jesus Christ" (Jude 1:4). Jude describes these folks in vivid terms. They "revile the things which they do not understand" (Jude 1:10). They "are grumblers, finding fault, following after their own lusts; they speak arrogantly, flattering people for the sake of gaining an advantage" (Jude 1:16). They "cause divisions, [and are] worldly-minded, devoid of the Spirit" (Jude 1:19).
This is a devastating assessment of people who are not outside the church but have "crept in unnoticed." Jude wants them be spotted for who they really are, so that the church is not deceived and ruined by their false teaching and immoral behavior.
One of his strategies is to compare them to other persons and events in history. For example, he says that "Sodom and Gomorrah . . . since they, in the same way as these, indulged in gross immorality and went after strange flesh, are exhibited as an example in undergoing the punishment of eternal fire" (Jude 1:7). So Jude compares these people to Sodom and Gomorrah. His point in doing this is to say that Sodom and Gomorrah are "an example" of what will happen when people live like these intruders are living. So, in Jude's mind, knowing the history of Sodom and Gomorrah is very useful in helping detect such error and deflect it from the saints.
Similarly in Jude 1:11, Jude piles up three other references to historical events as comparisons with what is happening in his day among Christians. He says "Woe to them! For they have gone the way of Cain, and for pay they have rushed headlong into the error of Balaam, and perished in the rebellion of Korah."
Taken from "The Value of Learning History: A Lesson From Jude" by Desiring God (used by permission).