Matthew 12:34
You brood of vipers! How can you speak good, when you are evil? For out of the abundance of the heart the mouth speaks. The brood of vipers epithet — previously applied by John the Baptist to the Pharisees and Sadducees (Matthew 3:7) — is now used by Jesus in direct address. The connection between the heart's content and the mouth's speech grounds the Beelzebul charge in the Pharisees' corrupted hearts: they cannot speak good because they are evil. The abundance of the heart principle makes the Beelzebul charge a self-disclosure of the Pharisees' inner condition.