Job 20:15,16 - Joseph Benson’s Commentary on the Old and New Testaments

He hath swallowed down riches He hath got possession of them, and thought them to be as much his own as the meat he had eaten. But he is deceived. He shall vomit them up again Shall be compelled to restore them: his own conscience perhaps may make him so uneasy in the keeping of what he has gotten, that, for the quiet of his own mind, he shall make restitution, and that not with the pleasure of a virtue, but with the utmost reluctancy, like the pain produced by an emetic. God shall cast them out of his belly If he do not himself voluntarily refund what he has violently taken away, God, by his providence, shall force him to do it, and bring it about, one way or other, that his ill-gotten goods shall return to their right owners. If man's hand cannot reach him, God shall find him out. He shall suck the poison of asps What he sucked so sweetly, and with so much pleasure, shall, in the issue, prove most ungrateful and destructive, as the poison, or head (for the Hebrew ראשׁ, rosh, signifies both, and the poison lies in the head) of asps would be to one that sucked it. Such is sin; such especially will all unlawful gains be. The fawning tongue will prove the viper's tongue. All the charming graces that are thought to be in sin will turn, when the conscience is awakened, into so many raging furies.