גַּ֥ם כָּל־יָמָ֖יו בַּחֹ֣שֶׁךְ יֹאכֵ֑ל וְכָעַ֥ס הַרְבֵּ֖ה וְחָלְי֥וֹ וָקָֽצֶף׃
All his days also he eateth in darkness, and he hath much vexation and sickness and wrath. .
Read Jewish philosophical commentary on Ecclesiastes 5:16: and classical philosophical sources.