נֵר־לְרַגְלִ֥י דְבָרֶ֑ךָ וְ֝א֗וֹר לִנְתִיבָתִֽי׃
אַ ליכט פֿאַר מײַן פֿוס איז דײַן װאָרט, און אַ ליכטיקײט פֿאַר מײַן שטעג.
Rashi
Your words are a lamp for my foot When I come to promulgate a decision of law, I look in the Torah and it separates me from [transgressing] the prohibition, like a lamp which saves a man from [falling into] the pits.