Commentary - Matthew 15:15-20

Bird's-eye view

In this passage, Jesus provides a much needed course correction for His disciples, and by extension, for all of us. The context is a confrontation with the Pharisees, who were majoring in the minors, obsessed with external washings and traditions while their hearts were far from God. Peter, speaking for the group, asks for a plain explanation of the parable Jesus had just used to rebuke them. Jesus' response cuts directly to the heart of the matter, literally. He explains that true defilement is not an external issue, something you can get on you like dirt on your hands. No, true defilement, the kind that separates a man from God, is an internal issue. It is a matter of the heart.

Jesus uses a simple biological reality to make a profound spiritual point. Food goes in the mouth, through the stomach, and out again. It is a physical process that does not touch the soul. But what comes out of the mouth, our words, our expressions, these originate in the heart. And it is from this fountainhead of the heart that all true wickedness flows. Jesus lists a representative sample of sins that defile a man, things like murder, adultery, and theft. These are not things that happen by accident; they are the rotten fruit of a corrupt heart. The passage concludes by circling back to the initial controversy, making it clear that eating with unwashed hands is a triviality compared to the profound corruption that resides within the unregenerate human heart.

Outline

Context In Matthew

This section is the climax of a conflict that began at the start of the chapter. The scribes and Pharisees from Jerusalem, the religious heavyweights, had challenged Jesus about His disciples transgressing the "tradition of the elders" by not washing their hands before eating. Jesus turned the tables on them, accusing them of transgressing the commandment of God for the sake of their tradition. He called them hypocrites, quoting Isaiah to show that their worship was external and their hearts were far from God.

After this public rebuke, Jesus called the multitude and taught them the principle that what goes into a man does not defile him, but what comes out does. The disciples, still thinking in the Pharisees' categories, are baffled. Peter's question in our text shows that they, too, were still caught up in the externalism of the day. Jesus' explanation here is therefore a foundational lesson in New Covenant ethics. He is shifting the entire focus from external, ceremonial purity to internal, moral reality. This is a radical departure from the religious framework of Second Temple Judaism and sets the stage for the gospel's emphasis on a new heart.

Verse by Verse Commentary

15 Now Peter answered and said to Him, “Explain the parable to us.”

Peter, as is often the case, acts as the spokesman for the twelve. He is blunt and to the point. He calls Jesus' teaching a "parable," which indicates that they found it obscure, a riddle. This is instructive. The disciples had just heard Jesus dismantle the theological framework of the Pharisees, but the truth of it had not yet sunk in. They were still thinking in terms of clean and unclean foods, of external regulations. They were looking for a new set of rules, when Jesus was pointing them to a new reality altogether. It is a good reminder that even those closest to Jesus can be slow on the uptake. Spiritual truth often needs to be unpacked for us, and we should not be ashamed to ask for the plain meaning, just as Peter did.

16 And Jesus said, “Are you still lacking in understanding also?

There is a note of loving exasperation in Jesus' voice here. "You too?" He had just dealt with the willful blindness of the Pharisees, but He expected more from His own disciples. They had been with Him, heard His teaching, and seen His works. They should have been getting it by now. This is not a harsh rebuke so much as it is a challenge. He is pushing them to move beyond a superficial hearing of His words and to engage their minds and hearts. The Christian faith is not a mindless affair. We are called to understanding. And when we are dull, as we all are at times, the Lord is patient, but He does expect us to grow.

17 Do you not understand that everything that goes into the mouth passes into the stomach, and goes into the sewer?

Jesus begins His explanation with the patently obvious. He appeals to basic human biology, something no one can dispute. Food is fuel for the body. It follows a predictable path and is eliminated. The process is entirely physical. It does not touch the non-material part of man, his heart, his soul, his spirit. By using this earthy, almost crude, illustration, Jesus is demolishing the entire edifice of ceremonial food laws as a means of achieving spiritual purity. The Pharisees had built a complex system of what could and could not be eaten, and how it must be prepared and consumed, all in an effort to maintain ritual cleanliness. Jesus sweeps it all away with one simple observation. Your diet does not make you right with God. What you eat goes to the sewer, not to your soul.

18 But the things that proceed out of the mouth come from the heart, and those defile the man.

Here is the central contrast and the main point of the lesson. True defilement is not an outside-in problem; it is an inside-out problem. The source of all spiritual pollution is the human heart. The "heart" in Scripture is not primarily the seat of emotion, but rather the center of the entire person: the will, the intellect, the affections. It is the command center of our being. And what comes out of the mouth, our words, are a reliable indicator of what is in the heart. As Jesus says elsewhere, "out of the abundance of the heart the mouth speaks" (Matt 12:34). Vicious words, lies, blasphemies, slanders, these are not just unfortunate slips of the tongue. They are leaks from a septic soul. These are the things that truly defile a man, making him unclean in the sight of a holy God.

19 For out of the heart come evil thoughts, murders, adulteries, sexual immoralities, thefts, false witness, slanders.

Jesus now provides a terrifying, but by no means exhaustive, list of the kind of filth that the human heart manufactures. Notice that He begins with "evil thoughts." All sin begins in the mind, in the heart. The overt acts of murder, adultery, and theft are simply the thoughts given legs. The heart conceives the sin, and then it is brought forth in action. This list is a direct echo of the Ten Commandments, showing that Jesus is not abolishing the moral law of God, but rather internalizing it. The Pharisees were concerned with not committing the physical act of murder. Jesus says the murderous thought, the hateful rage in the heart, is what defiles you. They were concerned with the act of adultery. Jesus says the lustful look is heart-adultery. This is a radical diagnosis of the human condition. Our problem is not that we occasionally break the rules. Our problem is that we have a corrupt nature, a heart that is a factory for sin.

20 These are the things which defile the man; but to eat with unwashed hands does not defile the man.”

Jesus concludes with a clear, summary statement. He brings the discussion full circle, back to the presenting issue of handwashing. The catalogue of sins He just listed, this is what true defilement looks like. This is what makes a person unfit for the presence of God. Compared to this profound inner corruption, the issue of whether you washed your hands before dinner is revealed to be utterly trivial. It is a non-issue. Jesus is not promoting poor hygiene. He is promoting proper theology. The Pharisees had inverted the moral order. They were meticulous about trivial externals while ignoring the massive corruption within. Jesus restores the proper perspective. God is concerned with the state of your heart, not the state of your hands.

Application

The first and most obvious application is that we must abandon all forms of external, self-righteous religion. It is a constant temptation for Christians to slip back into a Pharisaical mindset, to define our righteousness by what we do or do not do externally, by our adherence to a set of man-made rules or traditions. We can have our own versions of handwashing, our own little checklists of piety that make us feel superior to others. Jesus obliterates this. True religion is a matter of the heart.

Secondly, this passage should drive us to our knees in repentance. If Jesus' diagnosis is correct, and it is, then we are all in deep trouble. Our hearts, by nature, are desperately wicked and factories of sin. We cannot fix this problem ourselves. No amount of rule-keeping or self-improvement can cleanse a polluted heart. This is why we need the gospel. We need a heart transplant, which is precisely what God promises in the New Covenant: "I will give you a new heart, and a new spirit I will put within you" (Ezek 36:26). Only the blood of Jesus Christ can cleanse us from the defilement that comes from within.

Finally, for the believer who has been given a new heart, this passage is a call to vigilance. While we have been positionally cleansed, the remnants of that old sinful nature still wage war within us. We must be diligent to guard our hearts, for from it flow the springs of life (Prov 4:23). We must pay attention to our thought lives, to the words that come out of our mouths, because they are a true gauge of our spiritual health. We are to walk in the Spirit, putting to death the deeds of the body, and cultivating the fruit of righteousness that comes from a heart made clean by the grace of God.