Where their worm does not die and the fire is not quenched.
This third repetition of the thought further confirms the seriousness of what is said. The Lord in no way allows people to soften the truth of eternal judgment or to accept it in an abstract way. If life is precious and the kingdom of God is priceless, then everything that endangers them must be removed radically. This word also shows that sin, if it remains unrepented, has eternal consequences.