Matthew 12:33-35

33 Either make the tree good, and his fruit good; or else make the tree corrupt, and his fruit corrupt: for the tree is known by his fruit.

34 O generation of vipers, how can ye, being evil, speak good things? for out of the abundance of the heart the mouth speaketh.

35 A good man out of the good treasure of the heart bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things.