( Also of interest might be Fire and Flood by Glenn Andrew Peoples)

Man as a descendant of Adam is uniformly spoken of in the Bible as a mortal being, and as a sinner doomed to perish, for the wages of sin is death. (Rom. vi. 23.) On the other hand immortality or deathlessness is always spoken of as belonging to God, or to such as on certain specified conditions He has declared His purpose to confer it. It is by overlooking this truth and assuming that the Bible teaches, that all men converted or unconverted are born into the world immortal beings, that such statements as the following are used to support the belief of the eternal existence of the wicked in misery! “He will burn up the chaff with unquenchable fire.” Matt. iii. 12. “If thy hand offend thee, cut it off: it is better for thee to enter into life maimed, than having two hands to go into Gehenna, into the fire that never shall be quenched.” Mark ix. 43.
The words “fire that never shall be quenched” in Mark ix. 43, are the same in the Greek as the unquenchable fire in Matt. iii. 12, and should have been similiarly rendered. Probably the reason for introducing the terms “never shall be quenched,” in translating Mark’s narrative was to render them more expressive of the idea of eternal torment, which the translators believed to be the final doom of impenitent sinners. Suppose however we use the rendering “unquenchable fire,” instead of “the fire that never shall be quenched,” it will still be thought by many expressive enough of the idea, that the unsaved shall be doomed to endure the most excruciating agonies throughout unending duration. If it could be demonstrated from the usage of the language, that the casting of a person into “unquenchable fire” necessarily implies the everlasting existence of that person, or that the words “unquenchable fire,” are in no other instance applied in Scripture to objects which we know do perish, then I confess we would be shut up to accept the doctrine of immortal misery, with all its weight of melancholy sadness unless it were elsewhere positively denied. If however on the other hand we find the same language applied to objects which we know have ceased to exist, then, surely we are bound to maintain in the absence of direct testimony to the immortality of impenitent men, that such language by no means expresses or implies the idea of unending being.
The phraseology which our Lord here employs was familiar to His auditors. From their childhood, we may presume they had frequented the synagogue on the Sabbath, where the Scriptures of the prophets were read in their hearing; and they must often have listened to these words of the Lord by the prophet Jeremiah, “If ye will not hearken unto me to hallow the Sabbath day, and not to bear a burden, even entering in at the gates of Jerusalem on the Sabbath day; then will I kindle a fire in the gates thereof, and it shall devour the palaces of Jerusalem, and it shall not be quenched. Jer. xvii. 27. No sane man will assert that these palaces and gates of Jerusalem are indestructible, because the fire that destroyed them is termed “unquenchable”, so far from that being the case, the figure is justly understood to represent their complete destruction. Jehovah kindled the flames and none could extinguish them, they would continue- to burn till their purpose was completely effected. Destruction, not preservation, is the idea meant to be conveyed, and why not also the same idea when the doom of the wicked is represented by the same language? Why affirm that they are indestructible because Jesus said, they shall be “burnt up like chaff in unquenchable fire”? The meaning of the words “unquenchable fire” may be further illustrated by the use which Eusebius the ecclesiastical historian, makes of them in recording the death of those who suffered at the stake, for their adherence to the Christ. In his History, Book VI Ch.41., he gives an account of those who suffered at Alexandria, “the first of these was Julian, a man afflicted with the gout and neither able to walk nor stand, who with two others that came with him, were arraigned. Of these the one immediately denied, but the other named Chronium,
suruamed Eunius and the aged Julian himself, having confessed the Lord were carried on camels throughout the city -a very large one as you know-and in this elevation were scourged, and finally consumed in an immense fire,” (puri asbesto,) the same term rendered “unquenchable fire” Matt, iii, 12 After these Epimuchius and Alexander, who continued for ‘” long time in prison from the scourges and scrapers were also destroyed in an immense fire (puri asbestos). These faithful witnesses by being cast into “unquenchable fire” were reduced to ashes, not tormented for ever and ever, and when Jesus uses the same terms to describe the fate of the incorrigible sinner, how can these terms be fairly understood to mean anything else? The language of Jesus no more expresses the indestructibility of sinners than does that of Eusebius express the deathlessness of those who for the truth’s sake were consumed at the stake. “Unquenchable fire” then, means fire that irresistibly destroys that which is committed to its action. Had the Saviour’s words been properly attended to, they would never have been used as an argument for the doctrine we are combating. Would any one who had not previously believed such a doctrine, even imagine that when Jesus alluding to the end of the wicked, said “He will burn up the chaff with unquenchable fire.” He taught His hearers that the wicked were unconsumable? Certainly not! It is the wicked who are like the chaff, and though the fire might never be quenched, in the most absolute literal sense the chaff would be consumed. Jesus positively asserts that it shall. The chaff He will burn up. What emblem more expressive of the complete destruction of the wicked? Dream not then, 0 impenitent sinner! that thou art an immortal. Unless thou yield thee to the love of God,and heartily believe the gospel of His Son, the Messiah, who loved thee and gave Himself for thee, perish thou must like chaff before quenchless flame. Ponder, I beseech thee, the love warning of Jesus. “God so loved the world, that He gave His only begotten Son, that whosoever believeth in Him might not perish, but have everlasting life.”
Not less expressive of entire destruction is the Saviour’s language recorded by Mark, which has been already quoted. “It is better for thee to enter into life maimed, than having two hands to be cast into Hell, into the fire that never shall be quenched, where the worm dieth not and the fire is not quenched.” The word here translated “hell” is in the Greek “Gehenna” or valley of Hinnom, a small valley at the southeast of Jerusalem. In this valley the idolatrous Israelites caused their children to pass through the fire to Moloch. After the captivity the place became an object of the greatest abhorrence on account of these abominations, and following the example of Josiah, 2 Kings xxiii. 10, they made it a receptacle for the filth of the city, the carcasses of animals and malefactors, and to prevent the deterious effects of the consequent putrefaction great fires were constantly kept burning; hence the valley was called Hennom’s valley of fire, or Gehenna of fire.” It was thus a noise some and hidious spot. Its lurid fires constantly burning and the loathsome worms feeding on the corpses, was indeed a fit and expressive picture of the most abhorrent and complete destruction. This view of the subject is confirmed by the closing sentences of Isaiah’s prophecy. Speaking of the future glory of the nation of Israel, and its capital Jerusalem, and the terrible overthrow of the opposing Gentiles, the prophet says, “Behold the Lord will come with fire, and with His chariots like a whirlwind to render His anger with fury, and His rebuke with flames of fire; for by fire and by His sword will the Lord plead with all flesh: and the slain of the Lord shall be many.” chap. lxvi. 15.-16. “And it shall come to pass from one new moon to another, and from one Sabbath to another, shall all flesh come to worship before Me, saith the Lord. And they shall go forth, and look upon the carcasses of the men that have transgressed against Me: for their worm shall not die, neither shall their fire be quenched; and they.shall be an abhorring unto all flesh. v. 23 -24. Doubtless the scene here depicted is one of real carnage, yet the language, “their worm shall not die, neither shall their fire be quenched,” is applied to the carcasses of dead men. Here we have a key to the language in Mark, which indeed is but a quotation from Isaiah, that would be familiar to the disciples of Jesus. So thinks Albert Barnes, though a believer in the immortality of the wicked. In his notes on
Mark ix. 44-46, he writes: ” This figure is clearly taken from Isaiah lxvi. 24. In describing the great prosperity of the kingdom of the Messiah, Isaiah says, that the people of God shall go forth and look upon the carcasses of the men who have transgressed against God. Their enemies shall be overcome. They shall be slain. The people of God shall triumph. The figure is taken from the heaps of the dead, slain in battle, and the prophet says that the number of them shall be so great that their worm-the worm feeding on the dead-shall not die, shall live as long as there are carcasses to be devoured; and that the fire which was used to burn the bodies of the dead, shall continue long to burn, and shall not be extinguished till they are consumed.” “The word “their” in the phrase “their worm,” is used merely to keep up the image or figure. Dead bodies putrifying in the valley would be overrun with worms, while the fire would not be confined to them but spread to other objects, kindled by combustibles through all the valley.”
It is rather remarkable that this writer after such a correct exposition of the language, should affirm that the picture represents, dreadful and eternal sufferinqs. Putrid decaying carcasses, the image , of dreadful and eternal suffering! The worm luxuriating on a painless corpse, an image of the most painful anguish! The consumption of dead bodies in the devouring flame a symbol of deathless spirits, tormented by fire which pains but cannot kill them! Oh, the blinding effects of heathen philosophy on the minds of those who submit to its teaching!
The words of God in defiance of all the laws of rhetoric and common sense, must be made to sustain the baseless theories of human imagination, and thus poor mortals condemned to everlasting destruction inflate themselves with the vain conceit of their immortality, echoing with true filial earnestness and joy, the words of the old serpent, the Devil -” Ye shall not surely die.” – W. Laing.