Matthew 12:33-37

Either make the tree good, and its fruit good; or make the tree corrupt, and its fruit corrupt: for the tree is known by its fruit. Ye offspring of vipers, how can ye, being evil, speak good things? for out of the abundance of the heart the mouth speaketh. The good man out of his good treasure bringeth forth good things: and the evil man out of his evil treasure bringeth forth evil things. And I say unto you, that every idle word that men shall speak, they shall give account thereof in the day of judgment. For by thy words thou shalt be justified, and by thy words thou shalt be condemned.