Proverbs 15:14 KJV
The heart of him that hath understanding seeketh knowledge: but the mouth of fools feedeth on foolishness.
Proverbs 15:14, King James Version
In context
13 A merry heart maketh a cheerful countenance: but by sorrow of the heart the spirit is broken.
14 The heart of him that hath understanding seeketh knowledge: but the mouth of fools feedeth on foolishness.
15 All the days of the afflicted are evil: but he that is of a merry heart hath a continual feast.