18 and he saith to them, 'So also ye are without understanding! Do ye not perceive that nothing from without entering into the man is able to defile him? 19 because it doth not enter into his heart, but into the belly, and into the drain it doth go out, purifying all the meats.' 20 And he said—'That which is coming out from the man, that doth defile the man; 21 for from within, out of the heart of men, the evil reasonings do come forth, adulteries, whoredoms, murders, 22 thefts, covetous desires, wickedness, deceit, arrogance, an evil eye, evil speaking, pride, foolishness; 23 all these evils do come forth from within, and they defile the man.'

Matthew Henry's Commentary on Mark 7:18-23

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.