Glossa Ordinaria — as excerpted in the Catena Aurea on Mark 7:14-23

“(non occ.) The meaning of which He points out, when He subjoins, for from within, out of the heart of men, proceed evil thoughts. And thus it appears that evil thoughts belong to the mind, which is here called the heart, and according to which a man is called good or bad, clean or unclean.”