Matthew 15:11, 17-19

Not what goes into the mouth defiles a man; but what comes out of the mouth, this defiles a man.”

Do you not yet understand that whatever enters the mouth goes into the stomach and is eliminated? But those things which proceed out of the mouth come from the heart, and they defile a man. For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies.