15:11 what comes out of the mouth. What one says is a reflection or product of what is inside (12:36, 37 note).
15:11 defiles Make ritually unclean.
15:11 what proceeds out of the mouth … defiles the man. People might defile themselves ceremonially (under the Old Covenant) by eating something unclean, but they would defile themselves morally by saying something sinful (cf. Jas 3:6). Here Jesus clearly distinguished between the law’s ceremonial requirements and its inviolable moral standard. Ceremonial defilement could be dealt with through ceremonial means. But moral defilement corrupts a person’s soul.
15:11 “It is not what enters into the mouth that defiles the man” This related primarily to the question of hand washing (cf. v. 20), but Mark 7:19 adds a phrase that related it to all foods (cf. Acts 10).
11. This epigram, which is the sum of Jesus’ public teaching on this issue, states a principle of inward religion which was destined in time to undercut for the Christian church the whole elaborate system of ceremonial purification of the Old Testament and of later Judaism. It remains sufficiently cryptic not to be perceived immediately in all its radical newness, and to need further explanation for the disciples. The focus on words is reminiscent of 12:33–37; words which come out of the mouth form an appropriate contrast to defilement from what goes into the mouth. As in his exposition of Christian obedience in 5:21–48, Jesus goes behind the outward act and the literal observance of regulations to what ‘proceeds from the heart’ (v. 18). His words suggest a view of ‘original sin’, i.e. that sin springs from what a man is in himself, not from his environment.
Ver. 11.—Not that which goeth into the mouth defileth a man. The word rendered “defileth” (κοινοῖ) means “renders common,” in opposition to ἁγιάζειν, “to separate” for God’s use; hence the verb, ethically applied, signifies “to contract guilt.” The rabbis taught that certain meats of themselves polluted the soul, made it abominable in God’s sight. This was a perversion of the law respecting clean and unclean food. The pollution or guilt arose, not from the nature of the meat, but from the eating of it in contravention of a positive command. It was the disobedience, not the food, which affected the soul. It is remarkable that these distinctions of meats still obtain among half the civilized inhabitants of the world—Buddhists, Hindoos, Mohammedans—and that one of the hardest tasks of Christian missionaries is to make men understand the non-importance of these differences. We do not see that Christ here abrogated the Levitical law, but he certainly prepared the way for its supersession and transformation. But he made no sudden and violent change in the constituted order of things. Indeed, some distinctions were maintained in apostolical times, as we read in Acts 10:14; 15:20, 29; and it was only gradually, and as circumstances made their observation impossible, that such ceremonial obligations were regarded as obsolete. It is, perhaps, with the view of not shocking inveterate prejudice, that he does not say, “No food whatever defileth,” but “That which goeth into the mouth” defileth not, referring especially to the notion above reprehended, that eating with unwashen hands polluted the food taken and the soul of the person who consumed it. Our Lord says nothing of excess, e.g. gluttony and drunkenness, which, of course, has a polluting and deteriorating effect on the moral nature (see Luke 21:34). But that which cometh out of the mouth. In the former sentence the mouth is regarded simply as the instrument for receiving food and preparing it for digestion; in this sentence it is considered as the organ of the heart, that which gives outward expression to inward thoughts and conceptions. Fillion distinguishes them as “la bouche physique, et la bouche morale.” Philo has well said, “The mouth is that by which, as Plato puts it, mortal things enter, and whence immortal things issue. For therein pass meat and drink, the perishable food of a perishable body; but from it proceed words, immortal laws of an immortal soul, by which the rational life is directed and governed” (‘De Mundi Opif.,’ § 40). Defileth a man. Pollutes his soul, not with merely ceremonial defilement, but intrinsically and morally. Of course, our Lord is referring to evil words, etc., as he explains in ver. 19. For the mouth may give utterance to God’s praise, words of love, sympathy, edification. But the evil in a man’s heart will show itself in his mouth; and the open expression will react on the wicked thought, and make it more substantial, deadly, and operative.
15:11 What goes into someone’s mouth does not defile them. Jesus tells a parable to illustrate his point. His parable addresses purity issues (see the “Jewish Purity Considerations and Regulations”), which are central to the Pharisees’ question in 15:2.
11 This key saying, though described as a “parable” in v. 15, is not particularly cryptic. It is more in the nature of a proverb or epigram (which also fall within the range of meanings of Greek parabolē), a pithy statement of a general truth which then needs to be applied more prosaically to specific cases. Matthew’s version is slightly more pithy than that of Mark, which specifies that the things coming in are things “outside the person,” while those coming out are “out of the person;” Matthew, on the other hand, makes it clear that both the coming in and the going out are via the mouth—food and words respectively (cf. 12:33–37 for the importance of the latter). Not all ritual defilement in the OT was by means of food, of course; one could also be defiled by disease (especially skin disease), by one’s own bodily secretions or by touching something or someone unclean. But the principle of externally contracted defilement is well illustrated by the Levitical food laws (Lev 11; cf. also 17:10–16), and it is this principle which Jesus is here setting aside, no less explicitly in Matthew’s rather smoother version than in Mark’s.37 True defilement is not external and ritual, but internal and moral, as vv. 17–19 will explain further. The statement is simple and clear; it is its practical implications for those brought up on the OT and rabbinic ideology of ritual purity which are far-reaching and which were bound to lead to controversy and division in a church which derived its heritage from Judaism.
 Sproul, R. C. (Ed.). (2005). The Reformation Study Bible: English Standard Version (p. 1386). Orlando, FL; Lake Mary, FL: Ligonier Ministries.
 MacArthur, J. F., Jr. (2006). The MacArthur study Bible: New American Standard Bible. (Mt 15:11). Nashville, TN: Thomas Nelson Publishers.