Apologetics

Understanding Jesus' Teaching on Lust and Adultery: A Christmas Message

In Matthew 5:27-30, Jesus says looking at someone with lust is already adultery in the heart — sin starts before the act. Here's what He says about the cure, and why grace outweighs any sin you carry.

Jeff Reed Sunday, December 14, 2025 5 min read

During the Christmas season, we often focus on joy, peace, and celebration. Yet sometimes God’s Word calls us to examine difficult topics that challenge our hearts and minds. In Matthew 5:27-30, Jesus addresses the serious issue of lust and adultery, teaching us profound truths about the nature of sin and the transformation He offers.

What Did Jesus Really Say About Adultery? Jesus begins by referencing the seventh commandment: “You have heard it said, ‘You shall not commit adultery.’” But then He adds His authoritative interpretation: “But I say to you, everyone who looks at a woman with lustful intent has already committed adultery with her in his heart.”

This wasn’t Jesus abolishing the law but fulfilling it. He was revealing the true intent behind God’s commandments - to protect the sanctity of marriage and transform our hearts from the inside out.

Why Does Jesus Speak With Such Authority? When Jesus says “You have heard it said… but I say,” He’s making a bold claim. Unlike other teachers who simply repeated tradition, Jesus speaks with divine authority because He is the fulfillment of the law. He gave the law originally, so He has the right to explain its deepest meaning.

The religious leaders of His time had twisted God’s commandments into mere external rules that allowed them to justify their behavior. Jesus cuts through this legalism to address the heart of the matter.

What Is the Source of Sin? God created us as sexual beings before sin entered the world. Sex is God’s good gift to humanity, not an invention of modern culture or media. The problem isn’t our sexuality itself, but how sin has twisted and corrupted what God intended for good.

Lust represents any legitimate desire that has been illegitimately pursued or expressed. Like any sin, it takes something good that God created and warps it into something destructive.

Our Hearts: Factories of Idols John Calvin observed that our hearts are like factories that never stop producing idols. We take good things and make them ultimate things, allowing them to control and consume us rather than enjoying them as gifts from God.

As one writer put it: “My sin never feels like sin to me. My sin feels like life to me.” This is why external rules alone cannot solve our problem - the transformation must come from within.

How Serious Is This Issue? Jesus uses shocking language to emphasize the seriousness of sin: “If your right eye causes you to sin, tear it out… If your right hand causes you to sin, cut it off.” While He’s speaking metaphorically, He’s making a crucial point about the deadly nature of sin.

Our culture often treats sexual sin as a joke or something everyone does. But Jesus reveals its true destructive power - it’s like cancer that spreads through our souls, destroying marriages, families, and ministries.

Beyond Sexual Lust This teaching applies to all forms of destructive desire. Whether it’s addiction to alcohol, gambling, shopping, or materialism, the principle remains the same: if you don’t want to end up in the wrong place, stop looking in that direction.

What’s the Solution for Sin? External rules and regulations cannot cure internal problems. The law can diagnose our condition, but only grace can heal it. Think of the law and grace as two different doctors - one identifies the disease, the other provides the cure.

Practical Steps for Victory While there’s no magic formula, several principles can help in the battle against sinful desires:

Be honest with yourself about your struggles
Cry out to God for help in overcoming sinful patterns
Find an accountability partner you can trust
Change your behavior - walk away from tempting situations
Ask God for higher, more noble callings to replace destructive desires

The key is that greater, more positive, Christ-like desires must drive out the sinful ones. You can’t simply stop a bad habit - you need something better to replace it.

What About Christmas Desires? During this season of gift-giving, it’s worth examining our own wish lists. What are your deepest desires this Christmas? Most of us don’t need more stuff - we need to get rid of things we already have.

While buying gifts for loved ones is wonderful, consider whether some of that money might be better invested in Kingdom work. As the apostle John warns, “Do not love the world or the things in the world… the world is passing away and also its lusts, but the one who does the will of God lives forever.”

The Greatest Gift of All The good news is that there is more mercy in Christ than there is sin in us. The grace of God is greater than any sin we could commit. Jesus came not to shame us but to redeem our desires and fill us with His joy.

He alone is the water that can satisfy our deepest thirst and longings. This is the greatest gift we could give anyone this Christmas - the message of hope, love, joy, and peace found in Jesus Christ.

Life Application This week, examine your heart honestly. What desires are controlling you? What are you looking at or pursuing that’s leading you away from God’s best for your life? Instead of trying to simply stop bad habits, ask God to give you higher, more noble desires that honor Him.

Consider these questions as you reflect on this message:

What is my deepest desire this Christmas season - is it for more stuff or for more of Jesus?
Are there areas where I’m trying to follow external rules rather than allowing God to transform my heart?
What practical steps can I take this week to turn away from tempting situations and toward Christ?
How can I invest in things that last forever - God, His Word, and the souls of people - rather than temporary pleasures?

Remember, following Jesus isn’t about perfect performance but about heart transformation. He offers forgiveness for past failures and power for future victory. The same grace that saved you is available to change you from the inside out.

Frequently asked questions

What did Jesus mean when he said looking at someone with lust is already adultery?

In Matthew 5:27-30, Jesus references the seventh commandment — 'You shall not commit adultery' — and then adds His authoritative interpretation: 'But I say to you, everyone who looks at a woman with lustful intent has already committed adultery with her in his heart.' Jesus wasn't abolishing the law; He was fulfilling it by exposing the true intent behind God's commandments. The religious leaders of His day had reduced God's commands to external rules they could technically keep while still harboring sin in their hearts. Jesus cuts through that legalism to address the heart itself. Adultery doesn't start at the act — it starts at the look, the fantasy, the desire pursued in the wrong direction. Jesus speaks with divine authority because He gave the law originally and has the right to explain its deepest meaning. The point is that God cares about what's happening inside us, not just our outward behavior. Sin is a heart problem, and only a transformed heart — not white-knuckled rule-keeping — can address it.

Why does Jesus talk about tearing out your eye or cutting off your hand?

Jesus uses deliberately shocking language — 'If your right eye causes you to sin, tear it out... If your right hand causes you to sin, cut it off' — to emphasize the deadly seriousness of sin. He's speaking metaphorically, not commanding self-mutilation, but He's making a crucial point: our culture treats sexual sin as a joke or as something everyone does, while Jesus reveals its true destructive power. Sin is like cancer that spreads through our souls, destroying marriages, families, and ministries. The metaphor calls for radical, decisive action against the sources of temptation in our lives. If you don't want to end up in the wrong place, stop looking in that direction. Walk away from tempting situations. Cut off the inputs that feed sinful desire. The metaphor matches the stakes — sin is worth treating with that kind of urgency.

How does a Christian actually overcome lust and sinful desires?

External rules and regulations cannot cure internal problems — the law can diagnose our condition, but only grace can heal it. There's no magic formula, but several principles help in the battle: be honest with yourself about your struggles, cry out to God for help, find a trusted accountability partner, change your behavior by walking away from tempting situations, and ask God for higher, more noble callings to replace destructive desires. The key principle is that you can't simply stop a bad habit — you need something better to replace it. Greater, more positive, Christ-like desires must drive out the sinful ones. John Calvin observed that our hearts are like factories that never stop producing idols, taking good things God created and making them ultimate things. The cure isn't trying harder; it's the grace of God transforming us from the inside out. There is more mercy in Christ than there is sin in us.

Is sex itself sinful according to the Bible?

No. God created us as sexual beings before sin entered the world. Sex is God's good gift to humanity, not an invention of modern culture or media. The problem isn't our sexuality itself, but how sin has twisted and corrupted what God intended for good. Lust represents any legitimate desire that has been illegitimately pursued or expressed. Like any sin, it takes something good God created and warps it into something destructive. Jesus' teaching on lust isn't anti-sex — it's pro-marriage and pro-human-flourishing. He's protecting the sanctity of marriage and calling for hearts that honor the gift God gave. The good news of the gospel is that Jesus came not to shame us but to redeem our desires and fill us with His joy. He alone is the water that can satisfy our deepest thirst and longings.

Jeff Reed

Pastoral writing from the team at Christchurch Miami — a faith family on mission in Kendall, Miami.

From the Message