John Gill Commentary Isaiah 1:31

"And the strong shall be as tow, and his work as a spark; and they shall both burn together, and none shall quench them." — Isaiah 1:31 (ASV)

And the strong shall be as tow
(Nwoxh) , "that strong one", who is eminently so; the little horn, whose look is more stout than his fellows, (Daniel 7:20) the beast who had great power and authority given by the dragon, (Revelation 13:2Revelation 13:4Revelation 13:7) who shall be cast alive into the lake of fire; when he will be like tow in those devouring flames, easily, quickly, and irrecoverably consumed, (Daniel 7:11) (Revelation 19:20)

and the maker of it as a spark ,
or "his work"; so the Targum,

``and the work of their hands shall be as a spark of fire;'' or like the embers and ashes of a coal, which are blown away and lost at once: so antichrist, and all his evil works, as well as all his evil workers under him, will be entirely consumed: or, as it may be rendered, "he that wrought him": that is, Satan, for his coming is after the working of Satan; he has his seat, power, and authority, from the dragon, the old serpent, and the devil, and may be truly called a creature of his, (2 Thessalonians 2:9)

and they shall both burn together ;
both the pope and the devil in the lake of fire and brimstone, into which they will both be cast, (Revelation 20:10)

and none shall quench [them] ;
that fire will be unquenchable and everlasting; they will be tormented for ever and ever, and so will all the worshippers of the beast, (Matthew 25:41) (Mark 9:44) (Revelation 14:11) (20:10) . The Chaldee paraphrase is, ``so the wicked shall be consumed, and their evil works, and there shall be no mercy upon them.''