There are only two possible eternal destinies for each person, and Revelation 21:7-8 contrasts the two. First, in verse 7, Jesus says:
He who overcomes shall inherit all things, and I will be His God and he shall be My son. (N.K.J.V.)
This brings up the all-important question: How does one overcome? We find that answer in 1 John 5:1,4-5, which says:
Whoever believes that Jesus is the Christ is born of God, and everyone who loves Him who begot also loves him who is begotten of Him…For whatever is born of God overcomes the world. And this is the victory that has overcome the world – our faith. Who is he who overcomes the world, but he who believes that Jesus is the Son of God? (N.K.J.V.)
So, when a person places his or her belief (faith) in Jesus Christ as Savior, that person becomes an “overcomer.” And all “overcomers” will spend eternity with Jesus. That is a promise.
But now let’s turn to the other potential destiny. Revelation 21:8 says:
But the cowardly, unbelieving, abominable, murderers, sexually immoral, sorcerers, idolaters, and all liars shall have their part in the lake which burns with fire and brimstone, which is the second death. (N.K.J.V.)
You say, “Well, I’m no coward. I’m not abominable. I’ve never murdered anyone. I’m not sexually immoral. I’m certainly not a sorcerer. I don’t have an idol that I worship. And I don’t lie.” Okay, I’ll give you credit for living a life of bravery and morality. But did you notice that the word “unbelieving” is also on that sordid list? And the “unbelief” in question relates to Jesus.
You see, even if you have the rest of the list covered, but you have not believed in Jesus as your personal Savior at your death, you will experience what the verse calls “the second death.” This “second death” is nothing less than spending eternity in “the lake which burns with fire and brimstone.” That is every bit as much a promise as the one about overcomers spending eternity with Jesus.
This is how high the stakes are concerning your belief (or lack of it) in Jesus as your personal Savior. Most people wouldn’t rate their unbelief in Jesus as a heinous sin on par with the likes of murder, sexual immorality, or sorcery, but God does. As a matter of fact, while those other sins will all be forgiven the moment a person does place saving belief in Jesus, there is no forgiveness to be found (in this life or in eternity) for the sin of refusing to yield such belief.