I. In vv10-11 Jesus says our problem is not what goes into us, but what is already inside of us. II. In vv12-14 Jesus straightforwardly tells his disciples the Pharisees and scribes can’t be trusted. III. vv15-18 What comes out of the mouth proceeds from the heart, and this defiles a person. IV. And so, in vv19-20, the heart of the problem is the problem of the heart.