Mar 7:19 Because it enters not into his heart, but into the belly, and goes out into the draught, purging all meats?
Alternative: Because it doesn't lead into a person's heart but into the belly where it goes out into the waste, cleansing everything that is eaten.
Christ uses this verse to explain his statement in Mar 7:15. It is a little different that the version that is in Mat 15:17. As always it is interesting because of the differences.
First, this verse refers to the Greek concepts of "belly" and "heart," which are both physical and metaphorical. The heart or the chest is the home of the higher emotions and impulses, while the belly is the home of the lower emotions and impulses. Christ uses this contrast a number of other places such as Mat 12:40. Symbolically, the belly is the physical body while the heart is the emotional relationship. These ideas run constantly through Christ teaching. Unlike later Christians, Christ attaches no guilt or shame with the physical body, but he makes it clear that humans are much more than their physical nature.
Here, the emphasis is on how the physical body cleans itself of its impurities. There is no "moral" taint from what we take in physically in the form of food. Consider this a contradiction of the idea that we are what we eat.
Another subtle idea here is that everything that is purely physical becomes foul. This is consistent with Christ's overarching theme that physical life is temporary. We may worry about the cleanliness of our food, but the larger reality is that everything that we eat eventually becomes foul inside of our bodies. The important point is that it doesn't mean that it becomes part of us. We are part of a natural process where physical impurities are separated from our bodies.
This may well be taken as symbolic of our separation from or physical lives. As we are part of the physical process transforming food that separates us from the waste, we are also part of a natural process transforming our spirits where we are eventually separated from our temporary, physical lives.
"Enters" is eisporeuô (eisporeuomai), which means "lead in," "go into," and "enter." It combines "eis," which means "in" with poreuô (poreuomai), which means "make to go," "carry," "convey," "bring," "go," "march," and "proceed."
Heart" is from kardia (kardia), which means "heart" and which we discuss in a larger Greek context here. It is a metaphor for "deep."
"Goes out" is from ekporeuô (ekporeuomai), which means "to make to go out," "to fetch out," and "to march out."
"Belly" is from the Greek, koilia, which means the "cavity within the body" (from the Greek, koilos, for "hollow"). It means both the belly, the intestines, and the womb. The word is also used to mean "excrement," which fills the hollow.
"Draught" is from aphedrôn (aphedron), which is a word that only appears in the NT here to describe a place for dumping human waste. It means literally "separate from sitting." A similar word was used in the Greek translation of Lev 12:5 to describe the separation of a woman bleeding after childbirth. The source seems to be a vulgar Macedonian word.
"Purging" is from katharizô (katharizo), which means "to clean," "to clear the ground of weeds," "prune away," "to remove dirt," and "to remove impurities." It is also used to describe the removal of the inedible parts from grain (winnowing), clearing weeds from a field, pruning a plant and so on.
"All manner of" is from the Greek pas (pas), which means "all," "every," "the whole," and "everything."
"Meat" is from brôma (broma), which means "that which is eaten," "food," and "meat."