If there was ever a time when we need a sobering reminder of what awaits the unbeliever, it is now and Jude is not ashamed to give it. He has just finished saying that "certain people have crept in unnoticed" (v4) and have perverted God's way to suit their own gain and the Devil's plans.
In verse 5 to 7, Jude identifies three groups of people from both Earth's and Heaven's history to substantiate his claim here.
Verse 5:
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.
He refers to the Exodus of the Israelites out of Egypt following their 430-year exile from the promised land (Ex 12:33-42). We see that Jesus led them as "The pillar of cloud by day and the pillar of fire by night" (Ex 13:21-22). Not all the Israelites who left Egypt entered the promised land, despite God's saving grace and love for his people, they still sinned and quickly fell into unbelief. None of the first generation entered the Promised Land, all were killed in the desert, including Moses himself (Deut 34:5).
Verse 6:
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 judgement of the great day.
This heavenly example brings home that God's judgement for disobedience is not just for a small portion of his creation, but for ALL his creation, angels included. This verse is likely referring to the passage in early Earth history in Genesis 6:1-4, where the "sons of God came in to the daughters of man and they bore children to them". This was pre-flood era, before Noah and before humanity's second chance. Even the angels of God are punished if they are sinful.
Verse 7:
... 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 life.
Sodom and Gomorrah, infamous cities (and the surrounding cities) were destroyed completely by God as a result of their sexual immorality (Gen 19:23-29). These cities were in the Promised Land and yet were destroyed for disobedience.
Here's the thing ...
A casual link to God's people is not a guarantee of heaven and eternal life! Sure there are examples in the bible where people who were not part of God's people were saved by God, but they blessed Abraham and so God returned in likeness, according to his covenant with Abraham.
Even if you go to church every Sunday (or more often if you do!), regularly give to the poor, keep the ten commandments, give a tenth of all you earn to the church, become a vicar or even go, live and work in the promised land, none of this is a guarantee of Heaven.
Think of it this way ...
If the sinful and disobedient Israelites, who were God's chosen people, who he, himself, rescued out of the hands of the Egyptians, all met their deaths in the desert because of their disobedience, or, if the disobedient heavenly angels are "kept in eternal chains under gloomy darkness until the judgement of the great day", or, if cities actually WITHIN the promised land are destroyed completely along with the surrounding cities in the valley because of their sexual immorality and disobedience, what chance do we have of entering heaven if we just have a 'casual' link to God and his people?
If anything, these verses are a stark reminder that hell is real and eternal and like the sinful Israelites, the disobedient angels and the amorous Sodomites, we all fail to live up to God's standards. We are all destined for hell!
What's the point then? Why bother about faith, about God, about how we live? If we are destined for the eternal punishment of hell, what can we do?
Jude gives us the answer to that as well in verse 5, "Jesus, who saved a people". Jesus was there in the wilderness with the sinful Israelites, actively saving his chosen people out of Egypt. He is here today doing exactly the same. Christ alone saves. Nothing else comes close. If you put your trust in some worldly concept, money, science, education none of it will help you.
He has promised that whoever turns toward him and trusts completely in his saving grace, they will enter Heaven with him (John 3:16).
