The heart of him that hath understanding seeketh knowledge: but the mouth of fools feedeth on foolishness.

Wesley's Notes

15:14 Foolishness - Wickedness is meat and drink to them.

Jamieson-Fausset-Brown Bible Commentary

14. (Compare Pr 10:21, 22). The wise grow wiser, the fools more foolish (Pr 9:9).

Matthew Henry's Concise Commentary

15:14. A wise man seeks to gain more wisdom, growing in grace and in the knowledge of Christ. But a carnal mind rests contented, flattering itself. 15. Some are much in affliction, and of a sorrowful spirit. Such are to be pitied, prayed for, and comforted. And others serve God with gladness of heart, and it prompts their obedience, yet they should rejoice with trembling.

Matthew Henry's Whole Bible Commentary

Verse 14

Here are two things to be wondered at:- 1. A wise man not satisfied with his wisdom, but still seeking the increase of it; the more he has the more he would have: The heart of him that has understanding, rejoices so in the knowledge it has attained to that it is still coveting more, and in the use of the means of knowledge is still labouring for more, growing in grace, and in the knowledge of Christ. Si dixisti, Sufficit, periisti-If you say, I have enough, you are undone. 2. A fool well satisfied with his folly and not seeking the cure of it. While a good man hungers after the solid satisfactions of grace, a carnal mind feasts on the gratifications of appetite and fancy. Vain mirth and sensual pleasures are its delight, and with these it can rest contented, flattering itself in these foolish ways.