Proverbs 12:23

23 A prudent man conceals knowledge, And a heart-fool proclaims imbecility. In 23a Pro 12:16 is repeated, only a little changed; also 16a corresponds with 23a, for, as is there said, the fool knows not how to keep his anger to himself, as here, that a heart-fool (cf. the lying mouth, 22a) proclaims (trumpets forth), or as Pro 13:16 says, displays folly without referring to himself the si tacuisses. To this forward charlatan blustering, which intends to preach wisdom and yet proclaims in the world mere folly, i.e., nonsense and imbecility, and thereby makes itself troublesome, and only to be laughed at and despised, stands in contrast the relation of the אדם ערוּם, homo callidus, who possesses knowledge, but keeps it to himself without bringing it forth till an occasion presents itself for setting it forth at the right place, at the right time, and to the right man. The right motive also regulates such silence as well as modesty. But this proverb places it under the point of view of prudence.

Note, 1. He that is wise does not affect to proclaim his wisdom, and it is his honour that he does not. He communicates his knowledge when it may turn to the edification of others, but he conceals it when the showing of it would only tend to his own commendation. Knowing men, if they be prudent men, will carefully avoid every thing that savours of ostentation, and not take all occasions to show their learning and reading, but only to use it for good purposes, and then let their own works praise them. Ars est celare artem - The perfection of art is to conceal it. 2. He that is foolish cannot avoid proclaiming his folly, and it is his shame that he cannot: The heart of fools, by their foolish words and actions, proclaims foolishness; either they do not desire to hide it, so little sense have they of good and evil, honour and dishonour, or they know not how to hide it, so little discretion have they in the management of themselves, Ecc 10:3.