Proverbs 16:23

23 The heat of the wise maketh his mouth wise, And learning mounteth up to his lips. Regarding השׂכּיל as causative: to put into the possession of intelligence, vid., at Gen 3:6. Wisdom in the heart produceth intelligent discourse, and, as the parallel member expresses it, learning mounteth up to the lips, i.e., the learning which the man taketh into his lips (Pro 22:18; cf. Psa 16:4) to communicate it to others, for the contents of the learning, and the ability to communicate it, are measured by the wisdom of the heart of him who possesses it. One can also interpret הוסיף as extens. increasing: the heart of the wise increaseth, i.e., spreads abroad learning, but then בּשׂפתיו (Psa 119:13) would have been more suitable; על־שׂפתיו calls up the idea of learning as hovering on the lips, and thus brings so much nearer, for הוסיף, the meaning of the exaltation of its worth and impression.

Solomon had commended eloquence, or the sweetness of the lips (Pro 16:21), and seemed to prefer it before wisdom; but here he corrects himself, as it were, and shows that unless there be a good treasure within to support the eloquence it is worth little. Wisdom in the heart is the main matter. 1. It is this that directs us in speaking, that teaches the mouth what to speak, and when, and how, so that what is spoken may be proper, and pertinent, and seasonable; otherwise, though the language be ever so fine, it had better be unsaid. 2. It is this that gives weight to what we speak and adds learning to it, strength of reason and force of argument, without which, let a thing be ever so well worded, it will be rejected, when it comes to be considered, as trifling. Quaint expressions please the ear, and humour the fancy, but it is learning in the lips that must convince the judgment, and sway that, to which wisdom in the heart is necessary.