More Than Someone Else's Marriage: The Seventh Commandment

This is not an easy commandment to talk about, and it won't be an easy one to read. Adultery has touched nearly every family in some way, whether through a spouse's unfaithfulness, a parent's, or a private battle with lust that's never been said out loud. If any of that describes you, I'm not writing this to pile on shame you've probably already carried for years. I'm writing it because God gave us this commandment for a reason, and the reason is better than the fear or the guilt that usually surrounds this subject.

The seventh commandment is short: "You shall not commit adultery." Four words in Hebrew. But to understand what it's actually protecting, and why Jesus takes it even further than most of us expect, we need to look at three things — what adultery really is, why God built marriage the way he did, and what repentance and healing actually look like when this commandment has already been broken.

Two Definitions You Have to Hold at Once

Start with the plain, specific definition. Adultery is sex with someone who is married to someone else, or sex you have while married to someone other than your spouse. That's the definition our society still basically holds, and it's close enough to the biblical one that we can work from it. Under the Ten Commandments, this is what's forbidden in the most direct sense.

But the Old Testament doesn't stop there. Other sexual sins — the law names several — aren't technically "adultery" by that narrow definition, yet Scripture treats them as falling under the same umbrella, the same basic offense against the design of marriage. And Jesus removes any doubt about how far this goes. Turn to the Sermon on the Mount:

"You have heard that it was said, 'You shall not commit adultery.' But I say to you that everyone who looks at a woman with lustful intent has already committed adultery with her in his heart."

Matthew 5:27–28

Jesus doesn't say lust is a lesser cousin of adultery. He says it is adultery, already committed, in the heart. And notice who he directs that statement to: men. Our culture, like the ancient world, has often treated adultery as mainly a men's issue, or mainly a women's issue, depending on the century. Jesus refuses both. He calls it a heart issue — which means it belongs to every person in the room, married or not, man or woman, whether or not you've ever physically acted on it. If you've measured your own faithfulness only by what your body has done and never by what your heart has wanted, this verse is not letting you off that easily.

The seventh commandment was never really a men's issue or a women's issue. It's a heart issue — which makes it everyone's issue.

Why This Commandment Exists: What God Built in the Garden

Every "you shall not" in the Ten Commandments has a positive underneath it — something God is protecting by forbidding its opposite. To find what the seventh commandment protects, you have to go back before the commandments existed at all, to the first marriage:

"Therefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh. And the man and his wife were both naked and were not ashamed."

Genesis 2:24–25

Three things stand out. First, marriage is the most important human relationship there is — more than the bond between a parent and a child, more than any friendship. "Leave father and mother, hold fast to your wife" ranks marriage above the relationships our culture often treats as more permanent or more sacred. Ephesians 5 builds the entire household on this same foundation: husbands loving wives as Christ loved the church. That's the weight this relationship is meant to carry.

Second, "one flesh" is the purpose of marriage, and it's bigger than sex alone, though sex is part of it. It's the picture of two people becoming, in some real sense, one new thing: bearing children who are literally made of both of them, yes, but also becoming a single unit that reflects something about how God multiplies his kingdom. Marriage was always meant to be one of the primary ways God fills the earth with people who know him — first through children, and now, under the new commission to make disciples, through the witness of a marriage that looks nothing like the broken ones around it. A husband and wife loving each other the way Scripture describes is a rare enough sight that people notice, and noticing draws them toward God.

Third — and this is the piece adultery destroys first — "naked and not ashamed" is a picture of being fully known and still fully accepted. Shame hides. That's its nature; it always has been, since the moment Adam and Eve first felt it and ran for cover. Marriage, as God designed it, is the one human relationship built for the opposite of hiding: to be seen completely, mistakes and all, and not be pushed away. That's why Scripture so often describes sex itself as "knowing" someone. Adultery doesn't just break a rule. It takes the one relationship built for being fully known, and replaces it with something built on secrecy.

What Repentance Actually Looks Like

If any part of this has been true in your life — whether it's an ongoing struggle with lust, a past act you've never confessed, or wounds from someone else's unfaithfulness — the gospel doesn't leave you with only a diagnosis. There's a path forward, and it has three steps.

Repentance: turning around, not just stopping

Repentance means turning a full 180 degrees — not just away from the sin, but toward the thing it was substituting for. If you're struggling with pornography, lust, or an affair, the turn isn't only "stop doing that." It's "turn back toward honoring your marriage, or toward honoring the marriage you'll one day have." And this is not something anyone does alone. If lust or pornography has a grip on you, that grip is real, often closer to an addiction than a decision, and it requires confession — to your spouse if you're married, and to people who can hold you accountable either way.

Forgiveness: for yourself, and from others

Scripture describes sexual sin as, in a particular way, a sin against your own body. That means part of this is receiving forgiveness for yourself, not just from a spouse or from God, though both of those matter too. And if you're the one who has been wronged, Jesus is equally direct: the way you forgive is the way you'll be forgiven. Holding onto unforgiveness doesn't wound the person who hurt you. It keeps wounding you.

Reconciliation: rebuilding what secrecy tore down

This is the slow part, and there's no shortcut through it. Trust that was broken by hiding gets rebuilt only by the opposite of hiding — sustained honesty, over years, not a single conversation. If someone confesses this struggle to you and asks for help, resist the urge to fix it quickly. Get resourced, listen far more than you advise, and understand you may be walking with them for a long season, not a single season. That patient, ongoing accountability is part of what it means to be a church at all.

A Commandment Meant to Point You Somewhere Better

It would be easy to hear all of this as only a warning, but that misses what God is doing with his commandments. He isn't handing you a list of things to avoid so your life will be smaller. He's protecting something he built to be extraordinary — a relationship where you can be fully known and still not be ashamed, where faithfulness becomes a living picture of the faithfulness he's shown to his own people. That's worth protecting. And if this commandment has already been broken in your life, in any of the ways we've talked about, that same faithful God is not finished with you. Repentance, forgiveness, and reconciliation are slow, but they are not out of reach.

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