Do you not see that whatever goes into the mouth passes into the stomach and is expelled?
Christ having proved that the disciples, in eating with unwashen hands, were not to be blamed, as transgressing the traditions and injunctions of the elders, comes here to show that they were not to be blamed, as having done any thing that was in itself evil. In the former part of his discourse he overturned the authority of the law, and in this the reason of it. Observe, I.
Commenting on Matthew 15:10-20
Do not ye understand,.... You must understand, you cannot be so ignorant, that whatsoever entereth in at the mouth, goeth into the belly, and is cast out into the draught? that is, that whatsoever food a man takes in at his mouth, he swallows down, and it is received into his stomach; which, having performed its office, the grosser parts go down into the belly...
Verse 17. Do not ye yet understand, etc. The meaning of this may be thus expressed: The food which is eaten does not affect the mind, and therefore cannot pollute it. The doctrine of the Pharisees, that neglect of washing and of similar observances defiles a man, cannot be true. Those things pertain to the body as much as food does, and they cannot affect the soul.