Is Lust the Same as Adultery?

Jesus said that anyone who looks at someone lustfully "has already committed adultery with her in his heart" (Matthew 5:28). So in God's eyes lust isn't a harmless private thought. It's adultery at the level of the heart, and it needs the same repentance and the same grace. That doesn't mean a lustful look does all the damage an affair does, and it's no excuse to act on it. It means God cares about where adultery starts.

Brad Straarup dealt with this head-on in his message Let's Talk About Sex, and he didn't water Jesus down: lust isn't merely like adultery. It is adultery of the heart. That's a hard word, but it's also a freeing one, because it shows you where the battle is actually won.

What did Jesus actually say about lust?

In the Sermon on the Mount, Jesus quoted the seventh commandment and then went further: "You have heard that it was said, 'You shall not commit adultery.' But I tell you that anyone who looks at a woman lustfully has already committed adultery with her in his heart" (Matthew 5:27-28).

Jesus does the same thing with anger a few verses earlier (Matthew 5:21-22). The law dealt with the outward act; Jesus goes to the source. Out of the heart come evil thoughts, adultery and sexual immorality (Matthew 15:19). If the heart is where sin starts, the heart is where God wants to do His work.

Jesus then tells His listeners to gouge out an eye or cut off a hand if it causes them to stumble (Matthew 5:29-30). He's not asking for self-harm. He's using strong language to say: take decisive action. Whatever feeds lust in your life, cut it off.

Is being attracted to someone a sin?

No. Noticing that someone is attractive isn't lust. God made us with desire, and He calls His creation "very good" (Genesis 1:31). Temptation isn't sin either. Jesus "has been tempted in every way, just as we are," yet He never sinned (Hebrews 4:15).

Lust is what happens when you take the thought and keep it, when you look at someone in order to want them sexually or imagine them that way. James describes the slide: people are "dragged away by their own evil desire and enticed. Then, after desire has conceived, it gives birth to sin" (James 1:14-15). The first glance is temptation. The second, lingering look is a choice.

If lust is adultery, is it as bad as an affair?

Before God, both are sin, and both need the cross. Nobody can say, "I've only looked, so I'm fine." But the consequences aren't the same. An affair breaks a vow, wounds a spouse, involves another person and can tear a family apart. So don't let the enemy talk you into the logic of "I've already sinned in my heart, so I might as well go through with it." That's exactly backwards. Jesus raised the standard to protect you, not to make the act seem inevitable.

Why does lust matter if nobody knows?

The lie is that it's private and doesn't hurt anyone. The truth is, it hurts you. Left unchecked, lust changes how you see people. You stop seeing them as images of God and start seeing them as someone you can take something from. Every person you see was made in God's image (Genesis 1:27). Lust trains you to forget that.

And it rarely stays small. Lust becomes a habit, the habit looks for more, and pornography is often the next step. From there it can lead to sex outside of marriage and, eventually, adultery. Nobody wakes up one day and lands in a hotel room with someone else's spouse. As Brad puts it, "It starts with that one look. It starts with the tab we didn't close."

Even in marriage, a heart trained by lust learns that sex is about taking. God designed it to be about giving, a picture of how Christ gave Himself for His church (Ephesians 5:25, 31-32).

How do you fight lust?

You won't win by willpower alone, but you're not left alone either. "No temptation has overtaken you except what is common to mankind. And God is faithful; he will not let you be tempted beyond what you can bear" (1 Corinthians 10:13). Here are some practical ways to take Jesus seriously:

• Make a decision ahead of time. Job said, "I made a covenant with my eyes not to look lustfully at a young woman" (Job 31:1). Decide what you'll do with your eyes before the moment comes.
• Cut off what feeds it. This is Matthew 5:29-30 in real life: the app, the show, the late-night scrolling, the conversation you enjoy a little too much. Starve the flesh and feed the spirit. "Walk by the Spirit, and you will not gratify the desires of the flesh" (Galatians 5:16).
• Run, don't negotiate. "Flee the evil desires of youth and pursue righteousness, faith, love and peace, along with those who call on the Lord out of a pure heart" (2 Timothy 2:22). Notice the last phrase. You're not meant to fight alone.
• Bring it into the light. "Therefore confess your sins to each other and pray for each other so that you may be healed" (James 5:16). Find one trusted, mature believer who can ask you hard questions.
• Fill your mind with something better. Think about "whatever is true, whatever is noble, whatever is right, whatever is pure" (Philippians 4:8). Scripture, prayer and worship reshape what you want over time (Romans 12:2).

If lust has become pornography or a pattern you can't break, please don't hide it. Talk to a pastor, and find a counselor who shares your faith. We always encourage that. Getting help isn't a sign of weak faith. It's what walking in the light looks like.

Frequently asked questions

Is looking at pornography adultery?

By Jesus' definition, pornography is lust with a screen. It turns people into products, and it trains the heart to take instead of give. Treat it as seriously as Jesus treats lust, and get help to walk away from it.

Can God forgive lust?

Absolutely. "If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness" (1 John 1:9). And "there is now no condemnation for those who are in Christ Jesus" (Romans 8:1). Forgiveness isn't the end, though. It's the start of a new way of seeing people.

What if I keep falling?

Get back up, and get help. "Though the righteous fall seven times, they rise again" (Proverbs 24:16). Shame tells you to hide; grace tells you to come back to Jesus and keep going.

A better yes

Jesus' words on lust can sound like a heavy rule. They're actually an invitation to a whole heart and a freer life. "When God says no to something, it's because He has a better yes." He isn't trying to keep something from you. He's keeping something for you.

This post comes from Brad Straarup's message, Let's Talk About Sex, part of the series It's Complicated.

You don't have to fight for purity on your own; plan a visit and find people who will fight alongside you.

Keep reading: Are Soul Ties Biblical?