The heart of the righteous studieth to answer: but the mouth of the wicked poureth out evil things.

Wesley's Notes

15:28 Studieth - He speaks considerately. The mouth - Not the heart; for he rashly speaks what comes into his mouth, without the direction of his heart or conscience.

Jamieson-Fausset-Brown Bible Commentary

28. (Compare Pr 15:14; 10:11). Caution is the fruit of wisdom; rashness of folly.

Matthew Henry's Concise Commentary

15:25. Pride is the ruin of multitudes. But those who are in affliction God will support. 26. The thoughts of wicked men offend Him who knows the heart. 27. The covetous man lets none of his family have rest or enjoyment. And greediness of gain often tempts to projects that bring ruin. 28. A good man is proved to be a wise man by this; he governs his tongue well.

Matthew Henry's Whole Bible Commentary

Verse 28

Here is, 1. A good man proved to be a wise man by this, that he governs his tongue well; he that does so the same is a perfect man, Jam. 3:2. It is part of the character of a righteous man that being convinced of the account he must give of his words, and of the good and bad influence of them upon others, he makes conscience of speaking truly (it is his heart that answers, that is, he speaks as he thinks, and dares not do otherwise, he speaks the truth in his heart, Ps. 15:2), and of speaking pertinently and profitably, and therefore he studies to answer, that his speech may be with grace, Neh. 2:4; 5:7. 2. A wicked man is proved to be a fool by this, that he never heeds what he says, but his mouth pours out evil things, to the dishonour of God and religion, his own reproach, and the hurt of others. Doubtless that is an evil heart which thus overflows with evil.