He shall vomit them up again, i.e. be forced to restore them with great shame and torment, as gluttons sometimes do loathe, and with grief and pain cast up, that meat which they have eaten and swallowed down with much greediness and delight. If no man's hand can reach him, God shall find him out, and punish him severely.
Related Commentaries of Job 20:15
Job 20:15
15 He hath swallowed down riches, and he shall vomit them up again: God shall cast them out of his belly.