“For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies.”
Matthew 15 begins with the Pharisees being offended that Jesus Christ’s disciples didn’t follow their traditions of ritual hand washing. This led Jesus to discuss not only their traditions, but the real source of defilement.
Jesus Christ told everyone, “Not what goes into the mouth defiles a man; but what comes out of the mouth, this defiles a man” (verse 11).
Peter asked Him to explain, and Christ showed what is truly important. If some dirt gets on our food, that’s just a physical thing that will be eliminated by the digestive system. But what comes out of our hearts reflects our spiritual condition. Eating dirt is nothing compared to breaking God’s laws.
This story is also covered in Mark 7, which is often misunderstood. This is explained in our article “Mark 7: Did Jesus Purify Unclean Meats?”
For more about how our thoughts and temptations lead to sin, see “Temptation.”