NOTES for Mar 7:14-24
The Savior's words that nothing entering the mouth can defile a person are sometimes interpreted to mean that there is nothing in the world that is unclean in itself, and that nothing can harm a person except what comes out of his own heart. Yet Jesus is speaking about why nothing entering the mouth can defile a person: it passes through the person and is thereby cleansed. This statement, strange at first glance, turns out to be quite logical if we keep in mind the second part of the explanation, which speaks about what comes out of the heart. It presupposes that if a person's heart stops spewing into the world everything the Savior lists, then nothing unclean will be able to defile him.
Of course, Jesus speaks about uncleanness not in the sense of sinfulness, but in the sense in which the Torah speaks about it: as a special kind of psychophysiological and spiritual state that hinders communion with God and obstructs sanctification. It is in this sense that certain kinds of food are called unclean, or non-kosher, in the Torah. They are not bad in themselves, but they are not suitable for a person who wants to live a full spiritual life.
Perhaps this was so before the coming into the world of the Messiah, who brought the Kingdom with Him. The Kingdom is where the concepts of cleanness and uncleanness truly become irrelevant, because the fullness of relationship with God there is completely different and cannot be compared with what existed before.
For a resident of the Kingdom, nature remains nature. Until a person's full transfiguration, his physiology remains what it was before. But it no longer has the same influence on a person's spiritual state that it once had. The process of digestion no longer interferes in spiritual life. On one condition: if the heart is pure and no filth comes from it. Just as it should be for a resident of the Kingdom.