Reference for Psalms 35:13

וַאֲנִ֤י ׀ בַּחֲלוֹתָ֡ם לְב֬וּשִׁי שָׂ֗ק עִנֵּ֣יתִי בַצּ֣וֹם נַפְשִׁ֑י וּ֝תְפִלָּתִ֗י עַל־חֵיקִ֥י תָשֽׁוּב׃

But as for me, when they were sick, my clothing was sackcloth, I afflicted my soul with fasting; And my prayer, may it return into mine own bosom.

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