20 Hell and destruction are never full; so the eyes of man are never satisfied.
Two things are here said to be insatiable, and they are two things near of kin–death and sin.
1. Death is insatiable. The first death, the second death, both are so. The grave is not clogged with the multitude of dead bodies that are daily thrown into it, but is still an open sepulchre, and cries, Give, give. Hell also has enlarged itself, and still has room for the damned spirits that are committed to that prison. Tophet is deep and large, Isa. 30:33.
2. Sin is insatiable: The eyes of man are never satisfied, nor the appetites of the carnal mind towards profit or pleasure. The eye is not satisfied with seeing, nor is he that loves silver satisfied with silver. Men labour for that which surfeits, but satisfies not; nay, it is dissatisfying; but satisfies not; nay, it is dissatisfying; such a perpetual uneasiness have men justly been doomed to ever since our first parents were not satisfied with all the trees of Eden, but they must meddle with the forbidden tree. Those whose eyes are ever toward the Lord in him are satisfied, and shall for ever be so.
– Matthew Henry Commentary