Food laws
The food laws as permanent covenant practice or as fulfilled and set aside — Mark's aside about declaring all foods clean, Peter's vision in Acts 10, and the Jewish and Messianic readings.
Leviticus 11:1-47
1Yahweh spoke to Moses and to Aaron, saying to them,
2“Speak to the children of Israel, saying, ‘These are the living things which you may eat among all the animals that are on the earth.
3Whatever parts the hoof, and is cloven-footed, and chews the cud among the animals, that you may eat.
4“ ‘Nevertheless these you shall not eat of those that chew the cud, or of those who part the hoof: the camel, because it chews the cud but doesn’t have a parted hoof, is unclean to you.
5The hyrax, because it chews the cud but doesn’t have a parted hoof, is unclean to you.
6The hare, because it chews the cud but doesn’t have a parted hoof, is unclean to you.
7The pig, because it has a split hoof, and is cloven-footed, but doesn’t chew the cud, is unclean to you.
8You shall not eat their meat. You shall not touch their carcasses. They are unclean to you.
9“ ‘These you may eat of all that are in the waters: whatever has fins and scales in the waters, in the seas, and in the rivers, that you may eat.
10All that don’t have fins and scales in the seas and rivers, all that move in the waters, and all the living creatures that are in the waters, they are an abomination to you,
11and you shall detest them. You shall not eat of their meat, and you shall detest their carcasses.
12Whatever has no fins nor scales in the waters is an abomination to you.
13“ ‘You shall detest these among the birds; they shall not be eaten because they are an abomination: the eagle, the vulture, the black vulture,
14the red kite, any kind of black kite,
15any kind of raven,
16the horned owl, the screech owl, the gull, any kind of hawk,
17the little owl, the cormorant, the great owl,
18the white owl, the desert owl, the osprey,
19the stork, any kind of heron, the hoopoe, and the bat.
20“ ‘All flying insects that walk on all fours are an abomination to you.
21Yet you may eat these: of all winged creeping things that go on all fours, which have long, jointed legs for hopping on the earth.
22Even of these you may eat: any kind of locust, any kind of katydid, any kind of cricket, and any kind of grasshopper.
23But all winged creeping things which have four feet are an abomination to you.
24“ ‘By these you will become unclean: whoever touches their carcass shall be unclean until the evening.
25Whoever carries any part of their carcass shall wash his clothes, and be unclean until the evening.
26“ ‘Every animal which has a split hoof that isn’t completely divided, or doesn’t chew the cud, is unclean to you. Everyone who touches them shall be unclean.
27Whatever goes on its paws, among all animals that go on all fours, they are unclean to you. Whoever touches their carcass shall be unclean until the evening.
28He who carries their carcass shall wash his clothes, and be unclean until the evening. They are unclean to you.
29“ ‘These are they which are unclean to you among the creeping things that creep on the earth: the weasel, the rat, any kind of great lizard,
30the gecko, and the monitor lizard, the wall lizard, the skink, and the chameleon.
31These are they which are unclean to you among all that creep. Whoever touches them when they are dead shall be unclean until the evening.
32Anything they fall on when they are dead shall be unclean; whether it is any vessel of wood, or clothing, or skin, or sack, whatever vessel it is, with which any work is done, it must be put into water, and it shall be unclean until the evening. Then it will be clean.
33Every earthen vessel into which any of them falls and all that is in it shall be unclean. You shall break it.
34All food which may be eaten which is soaked in water shall be unclean. All drink that may be drunk in every such vessel shall be unclean.
35Everything whereupon part of their carcass falls shall be unclean; whether oven, or range for pots, it shall be broken in pieces. They are unclean, and shall be unclean to you.
36Nevertheless a spring or a cistern in which water is gathered shall be clean, but that which touches their carcass shall be unclean.
37If part of their carcass falls on any sowing seed which is to be sown, it is clean.
38But if water is put on the seed, and part of their carcass falls on it, it is unclean to you.
39“ ‘If any animal of which you may eat dies, he who touches its carcass shall be unclean until the evening.
40He who eats of its carcass shall wash his clothes, and be unclean until the evening. He also who carries its carcass shall wash his clothes, and be unclean until the evening.
41“ ‘Every creeping thing that creeps on the earth is an abomination. It shall not be eaten.
42Whatever goes on its belly, and whatever goes on all fours, or whatever has many feet, even all creeping things that creep on the earth, them you shall not eat; for they are an abomination.
43You shall not make yourselves abominable with any creeping thing that creeps. You shall not make yourselves unclean with them, that you should be defiled by them.
44For I am Yahweh your God. Sanctify yourselves therefore, and be holy; for I am holy. You shall not defile yourselves with any kind of creeping thing that moves on the earth.
45For I am Yahweh who brought you up out of the land of Egypt, to be your God. You shall therefore be holy, for I am holy.
46“ ‘This is the law of the animal, and of the bird, and of every living creature that moves in the waters, and of every creature that creeps on the earth,
47to make a distinction between the unclean and the clean, and between the living thing that may be eaten and the living thing that may not be eaten.’ ”
Mark 7:14-19
14He called all the multitude to himself, and said to them, “Hear me, all of you, and understand.
15There is nothing from outside of the man, that going into him can defile him; but the things which proceed out of the man are those that defile the man.
16If anyone has ears to hear, let him hear!”
17When he had entered into a house away from the multitude, his disciples asked him about the parable.
18He said to them, “Are you also without understanding? Don’t you perceive that whatever goes into the man from outside can’t defile him,
19because it doesn’t go into his heart, but into his stomach, then into the latrine, making all foods clean?”
What each tradition says
Rabbinic / Midrashic
According to this source, the dietary laws extended the priestly prohibition of unclean food to all Israel, so that the people could be impressively set forth as "a kingdom of priests and a holy nation." This priest-idea is the only possible meaning of Leviticus 20:25–26, where God says, "I have separated you from the peoples, that ye should be mine."
Solomon Schechter, Julius H. Greenstone, Emil G. Hirsch, Kaufmann Kohler (1901-1906), The Jewish Encyclopedia, vol. 4, s.v. 'Dietary Laws' (New York: Funk & Wagnalls) — section 'Priestly Sanctity of the Nation'
Patristic
Novatian states that the illustrious Master, the heavenly Teacher, and the ordainer of the perfected truth has come. Under him it is rightly said: to the pure all things are pure, but to the defiled and unbelieving nothing is pure; even their mind and conscience are defiled.
Novatian (c. 200-258), On the Jewish Meats (trans. R. E. Wallis), in Ante-Nicene Fathers, vol. 5 (Buffalo: Christian Literature Publishing Co., 1886) — Chapter V (on the limit of the shadows, 'the end of the law, Christ, came')
Catholic
Aquinas states that the mystery of human redemption was fulfilled in Christ's Passion, for Our Lord then said, "It is consummated." Consequently the prescriptions of the Law had to cease then altogether, their reality being fulfilled.
Thomas Aquinas (1225-1274); trans. Fathers of the English Dominican Province, Summa Theologica, Prima Secundae (I-II), q. 103, 'The Duration of the Ceremonial Precepts' (New York: Benziger Bros., 1947) — q. 103, art. 3, reply to objection 2
Orthodox
Chrysostom says that in this passage Jesus takes occasion from the previous topic to insert something greater: He casts out the observance of meats. He does so only after cleansing the leper, repealing the Sabbath, showing Himself King, making laws, remitting sins, raising the dead, and giving many proofs of His Godhead.
John Chrysostom (c. 349-407), Homilies on the Gospel of Saint Matthew (trans. George Prevost; rev. M. B. Riddle), in Nicene and Post-Nicene Fathers, ser. 1, vol. 10 (Edinburgh: T&T Clark, 1888) — Homily LI, section 3 (on Matthew 15:1-20)
Reformed / Protestant
Matthew Henry holds that one great purpose of Christ's coming was to set aside the ceremonial law God made and end it. Christ begins with the ceremonial law men had added, discharging his disciples from its obligation, which he fully does here because the Pharisees took offense at its violation.
Matthew Henry (1662-1714), An Exposition of the Old and New Testament, vol. 5 (Matthew to John) (London, 1706-1710) — Exposition of Mark 7:14-23, opening of the 'Worst Defilement from Within' section
Evangelical
Ryle says the Pharisees made holiness depend on meats, drinks, and bodily washings, treating those who kept their traditions as clean and those who neglected them as unclean. Jesus overturned this by showing that defilement comes not from outside a person but from within.
J. C. Ryle (1816-1900), Expository Thoughts on the Gospels: St. Matthew (London: Wertheim, Macintosh & Hunt, 1856) — section on Matthew 15:10-20