The mouth of the righteous speaketh wisdom. (On the essential union of wisdom with goodness, see the Proverbs, passim.) And his tongue talketh of judgment; i.e. utters only what is morally right, and,, in accordance with' truth and goodness.
Out of the abundance of the heart the mouth speaketh." A good man out of the good treasure of his heart can only bring forth good things (Matthew 12:34, Matthew 12:35).