15 There is nothing outside the man which, going into him, is able to make him unclean: but the things which come out of the man are those which make the man unclean. 16 [] 17 And when he had gone into the house away from all the people, his disciples put questions to him about the saying. 18 And he said to them, Have even you so little wisdom? Do you not see that whatever goes into a man from outside is not able to make him unclean, 19 Because it goes not into the heart but into the stomach, and goes out with the waste? He said this, making all food clean.
Matthew Henry's Commentary on Mark 7:15-19
Commentary on Mark 7:14-23
(Read Mark 7:14-23)
Our wicked thoughts and affections, words and actions, defile us, and these only. As a corrupt fountain sends forth corrupt streams, so does a corrupt heart send forth corrupt reasonings, corrupt appetites and passions, and all the wicked words and actions that come from them. A spiritual understanding of the law of God, and a sense of the evil of sin, will cause a man to seek for the grace of the Holy Spirit, to keep down the evil thoughts and affections that work within.