Proverbs 15:2
"The tongue of the wise useth knowledge aright: but the mouth of fools poureth out foolishness."
Cross References (ranked by relevance)
A prudent man concealeth knowledge: but the heart of fools proclaimeth foolishness.
The heart of the righteous studieth to answer: but the mouth of the wicked poureth out evil things.
Every prudent man dealeth with knowledge: but a fool layeth open his folly.
My heart is inditing a good matter: I speak of the things which I have made touching the king: my tongue is the pen of a ready writer.
The heart of the wise teacheth his mouth, and addeth learning to his lips.
Behold, they belch out with their mouth: swords are in their lips: for who, say they, doth hear?
The Lord GOD hath given me the tongue of the learned, that I should know how to speak a word in season to him that is weary: he wakeneth morning by morning, he wakeneth mine ear to hear as the learned.
A man hath joy by the answer of his mouth: and a word spoken in due season, how good is it!