What does Jude 1:5 mean?
In this verse Jude reminds his readers about what happened after the Lord rescued the Hebrews from slavery in Egypt. A massive nation of Israelites left Egypt and were accompanied by many non-Israelites (Exodus 12:37–38). During their journey through the desert, on their way to Canaan, the Promised Land, a rebellious number of them, called "rabble" in Numbers 11:4, caused Israel to complain about the Lord's provision. God had given them manna: a food from heaven. By complaining, they showed they did not believe in the Lord or in His ability to provide for their needs. They expressed their regret that they had left Egypt and voiced their desire to return there.Psalm 78:32 says that in spite of all God's mighty works on behalf of the people in the desert, "they still sinned…they did not believe." Later, these complainers rejected the Lord's command to enter the Promised Land. As a result of their unbelief, the Lord wiped them out (Numbers 14; Hebrews 3:16–19). The complainers died in the desert.
The apostates of Jude's days had heard the truth, and had seen God save souls, yet they refused to believe. Hebrews 3:7–12 offers a warning against similar apostasy: "Therefore, as the Holy Spirit says, 'Today, if you hear his voice, do not harden your hearts as in the rebellion, on the day of testing in the wilderness, where your fathers put me to the test and saw my works for forty years. Therefore I was provoked with that generation, and said, "They always go astray in their heart; they have not known my ways." As I swore in my wrath, "They shall not enter my rest." Take care, brothers, lest there be in any of you an evil, unbelieving heart, leading you to fall away from the living God.'"