Matthew 5:27-30

Bird's-eye view

As Jesus continues His great sermon, He follows the same pattern we saw in His teaching on murder. He takes a commandment that the Pharisees had domesticated, turning it into a mere external rule, and He restores its original force and depth. The issue is never just about the outward action; it is always about the heart. God's law is not a chain link fence to keep sinners from wandering off the reservation. It is a diagnostic tool that reveals the true location of our loyalties. Here, the Lord Jesus takes up the seventh commandment and demonstrates that the sin of adultery is not something that begins in a bedroom. It begins in the heart, with a look, with a desire. He then follows this diagnosis with a prescription for radical, wartime surgery. The stakes are heaven and hell, and so the measures we take against our sin must be correspondingly severe. This is not a call for self-mutilation, but rather for a ruthless spiritual violence against our own indwelling sin.

Outline

Clause-by-Clause Commentary

Verse 27: “You have heard that it was said, ‘YOU SHALL NOT COMMIT ADULTERY’;"

Jesus begins, as He did before, by citing the established teaching. "You have heard that it was said..." He is quoting the seventh commandment from Exodus 20:14. The Pharisees and scribes who taught the people had reduced this to a simple prohibition of the physical act of sexual intercourse with someone other than your spouse. So long as you didn't cross that particular line, you could congratulate yourself on your righteousness. You could be a respectable, law-abiding citizen. But this is a shallow and self-serving reading of God's law. It turns righteousness into a checklist of external behaviors, allowing the heart to remain a cesspool of filth. Jesus is about to take this tidy, manageable little rule and show that it has teeth, and that its bite is far worse than they had imagined.

Verse 28: "but I say to you that everyone who looks at a woman to lust for her has already committed adultery with her in his heart."

Here is the great intensification. "But I say to you..." Jesus is not contradicting Moses or setting aside the law. He is restoring the law to its intended place as a discerner of the thoughts and intents of the heart. The issue is not just the act, but the appetite. The verb "looks" here is not a passing glance or an accidental recognition of beauty. God made beauty, and it is not a sin to notice it. The Greek implies a deliberate, focused gaze, a looking with the purpose of cultivating desire. To look "to lust" is to look with the intent to possess, to consume in the imagination what you cannot have in reality. This is covetousness with a sexual charge. Jesus says this man "has already committed adultery with her in his heart." The sin is consummated in the heart long before it ever has the opportunity to be consummated in the flesh. The heart is the crime scene. This tells us that God judges the desire, not just the deed. He is the Lord of the conscience, the searcher of hearts. This is devastating news for every last one of us, for who can claim to be innocent on this count? This verse is designed to strip us of all self-righteousness and show us our desperate need for a righteousness that comes from outside of ourselves.

Verse 29: "But if your right eye makes you stumble, tear it out and throw it from you; for it is better for you to lose one of the parts of your body, than for your whole body to be thrown into hell."

Having exposed the disease, Jesus now prescribes the treatment. And the treatment is brutal. The "right eye" is singled out, likely because it was considered the more valuable eye. The eye is the gateway for the lustful look He just described. If the very organ you use to invite sin in is leading you to damnation, then get rid of it. Now, this is obviously hyperbole. Jesus is not commanding literal self-mutilation. If you plucked out your right eye, you could still lust with your left. And if you plucked out both, you could still lust in your imagination. The point is not about the physical organ, but about the source of temptation. The language is stark and violent because the spiritual reality is stark and violent. We are in a war. Sin is not a pet to be managed; it is an enemy to be killed. Jesus says it is "better" to enter eternal life maimed than to go to hell whole. He is teaching us a kind of spiritual triage. You must be willing to make a radical amputation of anything in your life that causes you to stumble into sin. This could be a subscription, a website, a particular route you take home from work, a friendship, anything. Whatever it is, you must be ruthless. The alternative is hell, and Jesus speaks of it as a real place where the whole body is thrown.

Verse 30: "And if your right hand makes you stumble, cut it off and throw it from you; for it is better for you to lose one of the parts of your body, than for your whole body to go into hell."

Jesus repeats the principle for emphasis, this time with the "right hand." The hand is the instrument of action. The eye sees, the heart desires, and the hand takes. If the eye is about the input of temptation, the hand is about the output of sin. Think of the modern equivalent: the hand that holds the smartphone, the hand that clicks the mouse. The principle is identical. Whatever you use to enact your sin, you must be willing to cut it off. Again, the logic is one of sanctified cost-benefit analysis. Is a few moments of fleeting, illicit pleasure worth an eternity in hell? The question answers itself. This is a call to holy violence against our own sin. We are to show it no mercy. We are to hack it off and throw it away. This is what Paul meant when he said to "put to death the deeds of the body" (Rom. 8:13). This is not something we can do in our own strength. This kind of radical surgery requires the grace of God and the power of the Holy Spirit. But the responsibility to take up the knife is ours. God will not do it for you, but He will empower you as you do it.

Application

The teaching of our Lord here is intensely practical. First, we must recognize that our fight for sexual purity is a fight of the heart. It is not enough to simply manage our external behavior. We must preach the gospel to our own affections and desires. We must confess the sin of lust as the heart-adultery that it is, and flee to Christ for cleansing.

Second, this requires us to be ruthless with ourselves. We live in a culture that is saturated with sexual temptation. To be holy in this environment requires a wartime mentality. You must identify your weak points, your stumbling blocks, and you must take drastic action. This means setting up real, practical boundaries. It means accountability. It means being willing to get rid of things that you may even think you have a "right" to. Your right to your smartphone is not as important as your fight for holiness. Your right to privacy is not as important as your eternal soul.

Finally, we must remember that this high and holy standard is meant to drive us to our knees. We cannot do this on our own. The law, as Jesus expounds it, is a schoolmaster that leads us to Christ. He is the only one who has ever lived with a perfectly pure heart. And through faith in Him, His righteousness is credited to our account, and His Spirit is given to us to enable us to begin to walk in this new way. The fight is hard, but in Christ, the victory is assured.