Isaiah 66:24
21 And I will choose some of them as priests and Levites,” says the Lord. 22 “For just as the new heavens and the new earth I am about to make will remain standing before me,” says the Lord, “so your descendants and your name will remain. 23 From one month to the next and from one Sabbath to the next, all people will come to worship me,” says the Lord. 24 “They will go out and observe the corpses of those who rebelled against me, for the maggots that eat them will not die, and the fire that consumes them will not die out. All people will find the sight abhorrent.”
Mark 9:48
43 If your hand causes you to sin, cut it off! It is better for you to enter into life crippled than to have two hands and go into hell, to the unquenchable fire. 44 If your foot causes you to sin, cut it off! It is better to enter life lame than to have two feet and be thrown into hell. 45 If your eye causes you to sin, tear it out! It is better to enter into the kingdom of God with one eye than to have two eyes and be thrown into hell, 46 where their worm never dies and the fire is never quenched. 47 Everyone will be salted with fire. 48 Salt is good, but if it loses its saltiness, how can you make it salty again? Have salt in yourselves, and be at peace with each other.”
Notes and References
"... what are the sources behind Mark 9:43-50, and what is their theological contribution to an understanding of this text; and what is the significance of this passage for the evangelist's eschatological expectations concerning the judgement of the wicked? In discussing the tradition-historical background, it becomes obvious that scriptural imagery and language play a dominant role in this Gehenna text. In the previous chapter we noted that the use of Gehenna in the Synoptics to denote the punishment of the wicked corresponds more to the book of Jeremiah than to contemporary usage. In addition to the allusion to Jeremiah, Mark 9:48 contains a direct quotation from Isaiah 66:24 ... In the last chapter Isaiah 66:24 is identified as one of the texts with strong similarities to Jeremiah's Ge-hinnom texts in picturing divine judgement in a valley - but unlike Jeremiah, Isaiah does not mention the valley by name ..."
Papaioannou, Kim Gary Places of Punishment in the Synoptic Gospels (p. 52) Durham University, 2004