(Proverbs 23:9) בְּאָזְנֵי כְסִיל אַל־תְּדַבֵּר כִּי־יָבוּז לְשֵׂכֶל מִלֶּיךָ׃
b’-oz-nay ch’-SEEL al-t’-da-BAYR ki-ya-VUZ l’-SAY-chel mi-LE-cha
Do not speak in the hearing of a fool, for they will despise the wisdom of your words.
The fool (כְסִיל) appears some 50 times in Proverbs. The fool is one step removed from the simpleton (פְּתָאיִם): whereas the simpleton can learn (e.g., 21:11), the fool is beyond that; a beating with a rod is what befits a fool (26:3). Part of being wise is discerning to whom to impart your wisdom. Sirach picks up on this understanding of the fool—”Whoever teaches a fool is like one who glues potsherds together” (Sir 22:9a)—that is, whoever teaches a fool wastes their time!
The idea that certain people are “unteachable” is not very welcome in our Western egalitarian-thinking society; nor is the idea of withholding counsel from those in peril. However, Proverbs (and Ben Sira) does not teach that fools cannot learn, but that they will not learn. ‘Simpletons’ may run into trouble because of their ignorance, and thereby the trouble can be diverted by offering them wise counsel; ‘fools’ are bound to suffer from the natural consequences of their actions because they refuse to receive any counsel. Wisdom dictates we hold our tongue and allow ‘the fool’ to learn by consequence rather than precept; we know this from experience because we’ve all played the fool at one time or another!