Matthew 12:34

Brood of vipers! How can you, being evil, speak good things? For out of the abundance of the heart the mouth speaks.

Surrounding context

12:33 "Either make the tree good and its fruit good, or else make the tree bad and its fruit bad; for a tree is known by its fruit.

12:34 Brood of vipers! How can you, being evil, speak good things? For out of the abundance of the heart the mouth speaks.

12:35 A good man out of the good treasure of his heart brings forth good things, and an evil man out of the evil treasure brings forth evil things.

Translation and sources