Matthew Henry's Complete Bible Commentary

Verse 21

Note, 1. It is the character of a wicked man that he takes pleasure in sin; he has an appetite to the bait, and swallows it greedily, and has no dread of the hook, nor feels from it when he has swallowed it: Folly is joy to him; the folly of others is so, and his own much more. He sins, not only without regret, but with delight, not only repents not of it, but makes his boast of it. This is a certain sign of one that is graceless. 2. It is the character of a wise and good man that he makes conscience of his duty. A fool lives at large, walks at all adventures, by no rule, acts with no sincerity or steadiness; but a man of understanding, the eyes of whose understanding are enlightened by the Spirit (and those that have not a good understanding have no understanding), walks uprightly, lives a sober, orderly, regular life, and studies in every thing to conform himself to the will of God; and this is a constant pleasure and joy to him. But what foolishness remains in him, or proceeds from him at any time, is a grief to him, and he is ashamed of it. By these characters we may try ourselves. MHBCC 644.23