Reference

John 3:18

He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God.
16

For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.

17

For God sent not his Son into the world to condemn the world; but that the world through him might be saved.

18

He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God.

19

And this is the condemnation, that light is come into the world, and men loved darkness rather than light, because their deeds were evil.

20

For every one that doeth evil hateth the light, neither cometh to the light, lest his deeds should be reproved.

Counter-Arguments

The strongest case that this verse does not belong in this theme.

Conditional Immortality (Hell context)

The verse states that those who do not believe are "condemned already," but it does not specify the nature or duration of this condemnation, nor does it explicitly mention anything about immortality or the lack thereof for the unsaved. The focus is on the state of condemnation rather than the state of existence.