Matthew 15:18

“But those things which proceed out of the mouth, etc.] Meaning not material things, as spittle, vomit, etc. but, as it follows, which come forth from the heart: are first conceived and formed there, and then come forth from thence, and are expressed by the mouth; as all idle words, foolish talking, filthy jesting, unsavoury communication, and every word that is rotten and corrupt, or which is done in the life and conversation; and they defile the man: the heart is the corrupt fountain from whence all moral defilement flows; and sinful words and actions are the impure streams, which spring from thence, and increase the moral pollution of human nature.”

“See also Mark 7:17-23. Then answered Peter, and said unto him, Declare unto us this parable - See the notes at Matthew 13:3. The word “parable” sometimes means a dark or obscure saying, Psalms 78:2. Peter meant, “Explain to us more fully this obscure and novel doctrine.” To us, now, it is plain; to the disciples, just coming out of Judaism, the doctrine of Jesus was obscure. Mark says that the disciples asked him. There is no contradiction. The question was put by Peter in the name of the disciples; or several of them put the question, though Matthew has mentioned only one. An omission is not a contradiction. Matthew 15:16 Are ye also yet without understanding? - Jesus appeals, in explaining…”

“Mat 15:11, Mat 12:34; Sa1 24:13; Psa 36:3; Pro 6:12, Pro 10:32, Pro 15:2, Pro 15:28; Luk 19:22; Jam 3:6-10; Rev 13:5, Rev 13:6 Matthew 15:19”