Like sheep they are laid in the grave; death shall feed on them. With the foolish fancies and vain conceits of the ungodly rich men, the psalmist now contrasts the reality. When they die they are "laid in the grave," or "ranged in Hades" (Kay), as sheep in a sheepfold.
There is no escape for them. Death is their shepherd; he keeps them, watches over them, tends them, allows none to quit the fold. And the upright shall have dominion over them in the morning. When the resurrection morn comes—and no other explanation appears to be possible (see even Cheyne)—it will bring them no release; the righteous will then "have domination over them," and will certainly not set them free (Revelation 21:8).
And their beauty shall consume in the grave from their dwelling; rather, and their beauty is for Hades to consume out of its dwelling; i.e. its clay tenement (so Dr. Kay).