כִּֽי־קִנְאָ֥ה חֲמַת־גָּ֑בֶר וְלֹֽא־יַ֝חְמ֗וֹל בְּי֣וֹם נָקָֽם׃
For jealousy is the rage of a man, And he will not spare in the day of vengeance.
Read halakhic rulings (Jewish law) on Proverbs 6:34 from the Mishneh Torah and classical halakhic sources, free online.