The hand, or the foot, or the eye represents any instrument by which sin may be committed; and it applies to those who may be the means of drawing us into sin. If your relative or your friend, who is useful or dear to you as your hand, your foot, or your eye, is drawing you into sin, cut him off from you, lest he should draw you into hell, into the unquenchable Gehenna.
Gehenna, or the Valley of Hinnom, lay to the south of Jerusalem. Originally a pleasant suburb of the city, it became in later times the scene of the worship of Molech, "the abomination of the children of Ammon."
On this account the valley was polluted by King Josiah. It thus became the receptacle of everything that was vile and filthy. These noisome accumulations were from time to time consumed by fire; and the things which were not consumed by fire were the prey of worms.
Hence "Gehenna" became the image of the place of eternal punishment, where "the worm dieth not and the fire is not quenched." These terrible images are conclusive as to the eternity of future punishment, so far as our nature is concerned and our knowledge reaches.
They are the symbols of certain dreadful realities; too dreadful for human language to describe or human thought to conceive.