Albert Barnes Commentary Proverbs 15:28

"The heart of the righteous studieth to answer; But the mouth of the wicked poureth out evil things." — Proverbs 15:28 (ASV)

Contrast the “studying” of the wise before he answers and the hasty babbling of the foolish. The teaching of our Lord (Matthew 10:19) presents us with a different and higher precept, resting upon different conditions.