Winning the Battle of the Mind

Topical Scripture: Matthew 5:27-30

When we follow Jesus, we die to the old life and live only for the new. In the Sermon on the Mount, Jesus teaches us how to live this new life, the biblical worldview, the life of a disciple. Today he deals with sexual sin and adultery.

Is this an issue for us?

Ninety-two million people visit porn sites every day. Pornography makes more money than the NFL, NBA, and Major League Baseball, combined. Twenty percent of men admit to having had an affair. I could add much more bad news.

The problem is clear, and real. How do we win the battle of the mind?

Refuse adultery of body (v. 27)

Our text begins: “You have heard that it was said, “Do not commit adultery” (v. 27). Here our Lord quotes the seventh commandment, cited specifically in Exodus 20:14 and Deuteronomy 5:18.

From the very beginning, God made clear to his creation that sexual activity within marriage is normal and good. In fact, he commanded it: “God blessed them…and said to them, ‘Be fruitful and multiply and fill the earth and subdue it'” (Genesis 1:28).

But God also made very clear that sex is his gift for marriage. Extramarital sex is always wrong: “If a man is found lying with the wife of another man, both of them shall die, the man who lay with the woman, and the woman. So you shall purge the evil from Israel” (Deuteronomy 22:22).

Premarital sex is as wrong as extramarital sex: “If there is a betrothed virgin, and a man meets her in the city and lies with her, then you shall bring both out to the gate of that city, and you shall stone them to death with stones, the young woman because she did not cry for help though she was in the city, and the man because he violated his neighbor’s wife. So you shall purge the evil from your midst” (Deuteronomy 22:23–24).

Sex is God’s gift for marriage. We are to refuse all adultery, of any kind. We are not to engage in sexual activity until we are married, and then with our spouse alone. This is the clear word and will of God.

Refuse adultery of mind (v. 28)

How do we keep this commandment? How do we resist sexual temptations, especially in a culture which so surrounds us with them every day? To refuse adultery of body, first refuse adultery of mind.

Aristotle was believed to have said “What is a crime for a person to do, is a crime for a person to think.” Jesus proves that this is so.

Our text continues: “But I say to you that everyone who looks at a woman with lustful intent has already committed adultery with her in his heart” (v. 28). The “I” here is emphatic—Jesus is asserting his own divine authority. This is just as much the command of God as the seventh commandment.

“Everyone”—regardless of religious title, status, or significance. No exceptions are granted here. “Who looks at”—the sin is not noticing a woman or a man. The sin is not the first look but the second. Luther was right: You cannot keep the birds from flying over your head, but you can keep them from nesting in your hair.

“A woman”—not specifically a wife, though this is implied. But adultery of the mind can be practiced with any woman, or with any man. “With lustful intent”—”who looks at a woman for the purpose of lusting.” Barclay translates the phrase, “Everyone who looks at a woman in such a way as to waken within himself forbidden desires for her.”

“Adultery with her in his heart”—the “heart” includes the intellect, the emotions, the will. The place from which actions find the origin. The source of all that follows. When we poison the mind, we poison the body. We poison the headwaters, which pollutes the river which flows out from them. The heart becomes the life.

Refuse the thoughts before they become actions. It will never be easier to refuse lust than when it first appears to your mind:

  • “I made a covenant with my eyes not to look lustfully at a girl” (Job 31:1 NIV).
  • “Do not lust in your heart after her beauty or let her captivate you with her eyes, for the prostitute reduces you to a loaf of bread, and the adulteress preys upon your very life. Can a man scoop fire into his lap without his clothes being burned? Can a man walk on hot coals without his feet being scorched? So is he who sleeps with another man’s wife; no one who touches her will go unpunished” (Proverbs 6:25–29 NIV).
  • Here’s how David’s sin started: “One evening David got up from his bed and walked around on the roof of the palace. From the roof he saw a woman bathing. The woman was very beautiful” (2 Samuel 11:2).
  • “Finally, brothers, whatever is true, whatever is honorable whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things…” (Philippians 4:8).

What if you cannot? What if there is an area or activity in your life which continually leads you into lust of the mind? Luther was picturesque: Don’t sit near the fire if your head is made of butter.

Here’s how Jesus advises us: “If the right eye causes you to sin, tear it out and throw it away. For it is better that you to lose one of your members than that your whole body be thrown into hell” (v. 29).

The “right eye” was considered the better of the two, as is the “right hand” in verse 30. If it “causes you to sin”—the phrase means specifically the stick in a trap which holds the bait; when the prey touches the stick, the trap snaps shut. So it is with the eye, which is the trap that baits the mind.

What are we to do with a sinful “eye”? Rabbinic hyperbole was a common teaching technique in Jesus’ day. The rabbis would teach a deliberate exaggeration to make a point. So it is here. Taken literally, one leaves the left eye with which to view lustfully. Take both eyes, but a blind man can still think sinful thoughts.

Jesus’ point is simple: rid yourself of anything which causes lustful thoughts in your mind. Premium channels on cable or satellite television; cable or satellite television; or even television. Use internet pornography filters on your computer, or even get rid of the internet itself. I have known of men and women who have changed their working relationships to avoid such temptation, and I admire them for their courage in doing so. Do whatever you must.

This is spiritual surgery—amputating the diseased limb to save the life of the patient. In this case, the soul. Because the malignancy is spreading.

Another illustration follows: “And if your right hand causes you to sin, cut it off and throw it away. For it is better that you to lose one of your members than that your whole body go into hell” (v. 30).

The right hand was indispensable for work in the ancient world. People typically saw the left hand as a symbol for evil, so they used it only for the most menial and demeaning tasks. Even today in many places in the East, to gesture to someone with the left hand is obscene.

Jesus’ point: get rid of anything you cannot control sexually. Anything which is causing you to lust must go. No matter how valuable you think it is. You would amputate your hand to save your life. So you must here.

Do it now. God’s word is clear: “Flee from sexual immorality. Every other sin a person commits is outside the body, but the sexually immoral person sins against his own body” (1 Corinthians 6:18). “So flee youthful passions and pursue righteousness, faith, love, and peace, along with those who call on the Lord from a pure heart” (2 Timothy 2:22). These are commandments from our holy God who is also our loving Father.


We have dealt today with a sober subject, but one which proves the continuing relevance of the Sermon on the Mount to life today. Refuse adultery of the body, extramarital and premarital sex. How? By refusing adultery of the mind. How? By refusing anything which leads you to such mental sin. Now.

Let me close with this fact: you cannot obey the teachings of this text alone. You were not meant to. There is not one word of the Sermon on the Mount which can be fulfilled in human ability. We must have God’s help to do God’s will.

So ask Jesus to deal with the source—your heart. Ask God to forgive your every sin and claim his cleansing and renewal: “If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness” (1 John 1:9).

Then stay close to Jesus. Stay connected to the source of your power by praying and worshiping all day long, communing with Christ: “If we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus his Son cleanses us from all sin” (1 John 1:7). When your enemy is shooting arrows at you, you’ll stay behind your shield.

Keep your mind focused on God: “Set your hearts on things above, where Christ is seated at the right hand of God … Put to death, therefore, whatever belongs to your earthly nature: sexual immorality, impurity, lust, evil desires and greed, which is idolatry” (Colossians 3:1, 5). And you will have the victory of God.

The same night our Lord shared the Lord’s supper with his disciples, he prayed three times in the Garden of Gethsemane not to have to go to the cross. Not just because of the physical torture, though it was beyond our imagining. Not just because our sins would be placed on his sinless soul, though we cannot imagine the horror he must have felt.

I think it was because when he took on our sin, for the only time in all of eternity, his intimate relationship with his holy Father was severed. In that moment, he cried out, “My God, my God, why have you forsaken me?” In that moment, he faced a pain and grief we cannot begin to understand.

But Jesus chose that. He did so for you and for me. He would do it all over again for us.

Please never again wonder if your Savior loves you, no matter your sins and failures. He will forgive all the past we confess and empower us to win victories in the future.