אִ֥ם תִּכְתּֽוֹשׁ־אֶת־הָאֱוִ֨יל ׀ בַּֽמַּכְתֵּ֡שׁ בְּת֣וֹךְ הָ֭רִיפוֹת בַּֽעֱלִ֑י לֹא־תָס֥וּר מֵ֝עָלָ֗יו אִוַּלְתּֽוֹ׃ (פ)
Though thou shouldest bray a fool in a mortar with a pestle among groats, Yet will not his foolishness depart from him.
Rashi on Proverbs
in a mortar Heb. במכתש, a mortar, in French mortier; Morser in German.
Rashi on Proverbs
with a pestle Heb. בעלי, a pestle, pilon in French, Stossel in German. Since they lift it up (מעלין) and beat with it, it is called עלי.