Proverbs 15:2 (NKJV) — 2 The tongue of the wise uses knowledge rightly, But the mouth of fools pours forth foolishness.
Using knowledge correctly. It is not enough to have knowledge; one must know how to use it. There is a right time and a right place to speak. Fools not only lack knowledge, but they lack control over their tongues. Foolishness pours out of their mouths.