From the Gospel according to Mark
MK 7:14-23

Jesus summoned the crowd again and said to them, “Hear me, all of you, and understand.  Nothing that enters one from outside can defile that person; but the things that come out from within are what defile.”

When he got home away from the crowd his disciples questioned him about the parable.  He said to them, “Are even you likewise without understanding? Do you not realize that everything that goes into a person from outside cannot defile,  since it enters not the heart but the stomach and passes out into the latrine?”  (Thus he declared all foods clean.)  “But what comes out of the man, that is what defiles him.  From within the man, from his heart,  come evil thoughts, unchastity, theft, murder, adultery, greed, malice, deceit, licentiousness, envy, blasphemy, arrogance, folly.  All these evils come from within and they defile.”