Charles Ellicott Commentary Proverbs 21:29

"A wicked man hardeneth his face; But as for the upright, he establisheth his ways." — Proverbs 21:29 (ASV)

A wicked man hardens his face—he is insensible to rebuke and will not confess that he is wrong, but the upright directs his way as God would have him, or, as the margin implies, “looks well” to it, sees that it is in accordance with His commandments.