What They Mean in Scripture
Mt.8:Verily I say unto you, I have not found so great faith, no, not in Israel. 11And I say unto you, That many shall come from the east and west, and shall sit down with Abraham, and Isaac, and Jacob, in the kingdom of heaven. 12But the children of the kingdom shall be cast out into outer darkness: there shall be weeping and gnashing of teeth
The weeping and gnashing of teeth is said to occur in outer darkness, which is the absence of light from God's grace. There the soul is able to remember what chance it had to enter the kingdom but would not. He countlessly remembers his sins that kept him out, the stubborness and refusal to repent and is tormented by it, described as "weeping and gnashing of teeth" . Even in this life, we see that humans experience this temporally at the loss of great opportunities that they passed up. They never forget them and are tormented by them.
In Mark 9, Christ uses the popular Rabbinic teaching of the worm of conscience, that "dieth not" and torments the wicked after death. Mk.9:. 43And 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 hell, into the fire that never shall be quenched: 44Where their worm dieth not, and the fire is not quenched. 45And if thy foot offend thee, cut it off: it is better for thee to enter halt into life, than having two feet to be cast into hell, into the fire that never shall be quenched: 46Where their worm dieth not, and the fire is not quenched. 47And if thine eye offend thee, pluck it out: it is better for thee to enter into the kingdom of God with one eye, than having two eyes to be cast into hell fire: 48Where their worm dieth not, and the fire is not quenched
In true far out fundamentalist fashion the SDA and Armstrong claim these are real worms. They simply haven't read or understand Jewish and Rabbinical teaching at the time of Christ. These worms were metaphors for the "worm of conscience" that would torment the wicked by their unrighteous deeds which they remembered for all eternity, that kept them from out of the kingdom of God.
Prisoners are often said to be tormented by their deeds. Like that of Scott Peterson, who wishes that he could take back that one moment, when he foolishly murdered his wife, and now must pay for it by countless hours of torment in prison for the single deed and never can he take it back. Likewise, the wicked are to always remember their deeds by which for the moment to fulfill the flesh will torment them by like the worm that eats at the conscience forever.
It's not a pretty picture but one finds that the things which occur on earth are examples of unto us of eternal truths, are taught in scripture. Let all men beware.