Does the biblical evidence fall on the side of eternal punishment in hell or annihilation?
If we restrict the question to what Scripture itself most naturally says, rather than what later Christian tradition came to teach, I think the evidence is more evenly divided than either side sometimes admits—but annihilation/conditional immortality has a surprisingly strong textual case.
The key issue is not whether final judgment is eternal. Scripture clearly presents it as irreversible and everlasting. The question is whether the wicked remain alive forever while being punished, or whether their punishment culminates in their final destruction/death.
The strongest evidence for annihilation
The ordinary vocabulary Scripture uses for the fate of the wicked repeatedly points toward death, destruction, perishing, and consumption, rather than perpetual conscious existence.
Jesus says:
“Fear him who can destroy both soul and body in hell.”
— Matthew 10:28
That is significant. The contrast isn’t “temporary body versus eternally tormented soul.” God can destroy both.
Likewise:
John 3:16: “should not perish, but have eternal life.”
That presents two contrasting destinies: perishing vs. eternal life. Paul uses essentially the same contrast:
Romans 6:23: “The wages of sin is death, but the free gift of God is eternal life.”
And:
2 Thessalonians 1:9: “They will suffer the punishment of eternal destruction.”
“Eternal destruction” can naturally mean a destruction whose result is eternal, just as “eternal redemption” (Heb. 9:12) doesn’t mean God is eternally in the process of redeeming us.
Jesus also repeatedly uses imagery of things being consumed:
“Every tree that does not bear good fruit is cut down and thrown into the fire.”
— Matthew 7:19
John the Baptist says the chaff will be burned with “unquenchable fire” (Matt. 3:12). Importantly, unquenchable doesn’t necessarily mean that the object burns forever. In the OT, an unquenchable fire is one no one can extinguish before it accomplishes its purpose (cf. Jer. 17:27).
Malachi’s imagery is even more striking:
“All the arrogant and all evildoers will be stubble. The day that is coming shall set them ablaze…. It will leave them neither root nor branch…. You shall tread down the wicked, for they will be ashes under the soles of your feet.”
— Malachi 4:1–3
That’s much closer to consumption than perpetual preservation in fire.
But there are serious texts for eternal conscious punishment
The strongest is unquestionably Matthew 25:46:
“And these will go away into eternal punishment, but the righteous into eternal life.”
The parallel is powerful: eternal punishment / eternal life. Traditionalists argue that if life continues eternally, punishment presumably does too.
The annihilationist response is that punishment can be eternal without punishing being eternal. Capital punishment, for example, is an act with a permanent consequence. Death from which there is no resurrection is genuinely an eternal punishment.
That response is linguistically possible, so Matthew 25:46 doesn’t settle the matter by itself.
Then there is Mark 9:48:
“where their worm does not die and the fire is not quenched.”
At first glance this sounds very much like eternal conscious torment. But Jesus is quoting Isaiah 66:24, and that’s crucial:
“They shall go out and look on the dead bodies of the men who have rebelled against me. For their worm shall not die, their fire shall not be quenched.”
Isaiah’s subjects aren’t immortal people consciously suffering. They are corpses being consumed. The undying worm and unquenchable fire emphasize the certainty and completeness of judgment.
That makes Mark 9 considerably less decisive for eternal conscious torment than it initially appears.
Revelation is where things become complicated
Revelation 14:10–11 says:
“He will be tormented with fire and sulfur…. And the smoke of their torment goes up forever and ever, and they have no rest, day or night.”
And Revelation 20:10 says of the devil, beast, and false prophet:
“they will be tormented day and night forever and ever.”
Those are probably the strongest biblical statements supporting eternal conscious torment.
But there’s an important distinction. Revelation explicitly says the devil, beast, and false prophet are tormented forever in 20:10. When humanity is judged a few verses later, John instead says:
“Then Death and Hades were thrown into the lake of fire. This is the second death, the lake of fire.”
— Revelation 20:14
The destiny of the wicked is repeatedly called death.
And given your caution about establishing doctrine primarily from apocalyptic imagery, Revelation 14 deserves especially careful handling. Its language comes heavily from Isaiah 34, where Edom’s judgment is described:
“Its smoke shall go up forever.”
— Isaiah 34:10
Edom obviously isn’t literally still burning. “Smoke rising forever” functions as prophetic imagery for permanent, irreversible destruction.
That OT background substantially weakens the argument that Revelation 14:11 must describe conscious suffering continuing endlessly.
One larger biblical pattern deserves more attention
There is another argument that I find particularly important: immortality is consistently presented as something God gives the redeemed, rather than something every human inherently possesses.
Paul says God:
“alone has immortality.”
— 1 Timothy 6:16
And believers:
“seek for glory and honor and immortality.”
— Romans 2:7
At the resurrection:
“this mortal body must put on immortality.”
— 1 Corinthians 15:53
Jesus says:
“whoever believes in him should not perish but have eternal life.”
— John 3:16
That creates an interesting theological problem for eternal conscious torment: Where does Scripture say that God grants immortality to the wicked so that they can remain consciously alive forever?
There may be arguments for it, but it is surprisingly difficult to find a passage that actually says it.
Where I think the evidence lands
If I were weighing only the biblical vocabulary, I’d put it this way:
Eternal conscious torment has a few very strong-looking texts, especially Matthew 25:46 and Revelation 14:10–11. But annihilationism has the broader cumulative vocabulary of Scripture: perish, destroy, destruction, death, second death, consumed, burned up, ashes—and the contrast between death and eternal life.
The OT backgrounds of Isaiah 34 → Revelation 14 and Isaiah 66 → Mark 9 make the annihilationist case considerably stronger still.
So I would lean toward conditional immortality/annihilation as the more natural synthesis, while not claiming that the case is airtight.
And I think there’s an important connection to the question you raised recently about whether Scripture actually teaches that every human soul is inherently eternal. If we begin with that assumption, eternal conscious torment follows rather naturally: the wicked cannot cease to exist, so their eternal judgment must involve eternal existence somewhere.
But if we don’t assume inherent immortality, the biblical language reads differently. “The wages of sin is death” can simply mean death, while “the gift of God is eternal life” means precisely what it says: immortal life is God’s gift in Christ.
That may actually be the more fundamental question than “What does hell do?”: Does Scripture teach that the lost possess immortality in the first place?