Albert Barnes Commentary Proverbs 29:11

"A fool uttereth all his anger; But a wise man keepeth it back and stilleth it." — Proverbs 29:11 (ASV)

Mind - The Hebrew word is used sometimes for “mind” or “reason,” sometimes for “passion,” or “wrath.” The reticence commended would include both; but the verb “keepeth it in” (rendered “stilleth,” in Psalm 65:7) is slightly in favor of the second of the two senses.