Fire on the Mountain: the Seventh Commandment
“Headwaters.”
That’s a helpful way to think about the Ten Commandments. They’re small, easy to miss if you’re not looking closely. But like the narrow streams high up in the mountains, they carry within them the beginnings of something massive. Rivers. Oceans.
The command we’re looking at might be the shortest of all:
“You shall not commit adultery.” (Exodus 20:14)
Just two words in Hebrew. Brief. Direct. But for many people, those two words aren’t small at all. They carry weight. History. Pain.
Almost everyone has a story connected to them.
Maybe it’s a marriage that fell apart.
Maybe it’s regret over something you wish you could undo.
Maybe it’s betrayal that still hasn’t healed.
Maybe it’s a private struggle no one else knows about.
Or maybe you’re just wondering why God would care so much about something our culture treats so casually.
So let’s be clear from the start. This isn’t about shaming anyone.
God’s law and God’s grace always work together. The law exposes what’s broken. The gospel heals what’s wounded. We need both. The bad news tells the truth about our condition. The good news tells the truth about God’s mercy.
And if we’re going to understand this commandment, we need to see it through that lens.
We Live Between Two Moments
The Christian life sits between two declarations.
“It is finished,” and “It is done.”
The first was spoken by Jesus on the cross. The second will be spoken at the end of history.
That means we’re living in the middle of a story that’s already been decided but not yet completed. We’re part of Christ’s kingdom now, but there’s more coming. The future is bright, but the present is still a fight.
We tend to forget that.
We drift. We lose sight of who we are. You could call it gospel amnesia. Like someone waking up without their memory, trying to piece together their identity from fragments.
That’s why Paul, in 1 Corinthians 6, keeps bringing believers back to three things:
Who you were
Who you are
Whose you are
If you lose those, everything else starts to unravel.
Remember Who You Were
Paul doesn’t sugarcoat the past.
“And that is what some of you were…” (1 Corinthians 6:11)
The Corinthians had messy lives. Sexual sin, broken relationships, distorted desires. Paul names it. He doesn’t pretend it’s fine.
But then comes one of the most important words in the Bible: “But.”
“But you were washed. You were sanctified. You were justified in the name of the Lord Jesus Christ and by the Spirit of our God.”
That one word changes everything.
The gospel doesn’t ignore the past. It interrupts it. It breaks into the present with a future we didn’t earn and don’t deserve.
You were something. But you’re not that anymore.
That matters, especially when we talk about sex. Because the Bible isn’t trying to shrink our view of it. It’s trying to restore it.
Remember Who You Are
Paul goes further.
“All things are lawful for me,” was apparently a positive slogan among the Corinthians; this was their freedom narrative about sex. In other words: I can do what I want.
It sounds familiar. It sounds very late-modern.
They treated sex like food. Just another appetite. “Food for the stomach and the stomach for food.”
Paul pushes back. Strongly.
Sex isn’t just physical. It’s spiritual.
It unites people.
It binds lives together.
And when it’s misused, it doesn’t become harmless. It becomes fragile. And often destructive.
We see this all around us.
The promise of unlimited freedom hasn’t delivered on its promise or fulfillment and flourishing.
People are more connected than ever and more alone than ever.
Commitment is declining. Relationships feel more like transactions than covenants.
Even outside the church, people are starting to notice.
We took something meaningful and reduced it to something casual. But stripping meaning doesn’t make something safe. It makes it shallow.
And shallow things break easily.
The Lie of Unlimited Freedom
There’s a mindset behind this.
“I can do whatever I want. There won’t be consequences.”
That idea isn’t new. It was alive in Corinth. It’s alive now.
You can see how it plays out in real life. Talent, success, and opportunity don’t protect anyone from it. In fact, they can make it worse. The more someone believes they’re untouchable, the more likely they are to cross lines they once thought they never would.
But reality always catches up.
Because sex is never “just sex.”
It’s never just an action. It’s a union. A giving of self. Even when people try to treat it casually, it still carries weight.
That’s why it leaves marks - emotional, relational, and spiritual.
What Happens When We Get It Wrong
Leo Tolstoy captured this better than most in Anna Karenina.
Anna leaves her husband for a passionate affair. At first, it feels like freedom. Like finally living honestly. Like breaking free from constraints.
But the story doesn’t stay there.
The relationship begins to unravel. What once felt exciting becomes heavy.
Jealousy creeps in.
Then paranoia.
Then isolation.
At one point, Tolstoy writes, “Everything was confusion in her soul.”
That’s what sin does. It promises clarity and delivers confusion.
By the end, Anna has everything she thought she wanted. But she’s lost something deeper:
Peace. Stability. Belonging. Hope.
The arc is painfully clear:
Attraction: “This is love.”
Affair: “This will make me happy.”
Defiance: “The rules are the problem.”
Possession: “I need complete control.”
Collapse: “Nothing makes sense anymore.”
It’s not just a story. It’s a pattern.
The Better Way We Overlook
Tolstoy doesn’t only show the collapse. He shows an alternative.
Another couple. Levin and Kitty.
Their relationship isn’t dramatic. It’s steady. Ordinary. Sometimes difficult.
But it grows.
Through forgiveness.
Through patience.
Through shared life.
At one point, Levin realizes something simple and profound:
“Love… is the only reasonable activity in the world.”
That’s what Scripture teaches, too.
The world celebrates passion. The Bible celebrates faithfulness.
Because real love isn’t built on intensity. It’s built on commitment.
And commitment is what gives love its depth.
Remember Whose You Are
Paul brings it to its deepest level.
“Your body is a temple of the Holy Spirit… You are not your own; you were bought at a price.” (1 Corinthians 6:19–20)
That’s a radically different way of seeing yourself.
Our culture says: “My body, my choice.” The gospel says: Your body matters more than you think. Not because you own it, but because Christ redeemed it.
And there are lies on both sides of this.
One side says:
It’s my body.
It doesn’t matter.
It’s just sex.
The other side says:
You’re dirty.
You’re ruined.
You can’t be forgiven.
Both are wrong.
The first minimizes sin. The second denies grace.
The gospel confronts both.
You were bought at a price. That means your life isn’t meaningless. And it also means your failures aren’t final.
The lies come in different forms:
“It’s nothing.”
“It’s just physical.”
“It’s a way to cope.”
“It’s who I am.”
“I can’t change.”
“I can’t be forgiven.”
They sound convincing. But they all distort reality.
Here’s the truth -
Sin always promises more than it delivers.
Grace always offers incomparably more than we can imagine.
The Gospel Rebuilds What Sin Breaks
This is where everything turns.
Christianity doesn’t just say “stop.” It says “remember.”
Remember:
You were rescued.
You are set apart.
You belong to Christ.
That changes how you see everything. Including your body. Including your relationships. Including your desires.
Because your identity isn’t based on your past.
It’s not based on your impulses.
It’s not based on how others define you.
It’s based on what Christ has done for you.
Living in That Identity
So what does that mean in real life?
It means you don’t offer parts of yourself to God. You offer your whole self.
Your thoughts.
Your habits.
Your relationships.
Your body.
Not as a burden. As a response.
Because Jesus didn’t give himself halfway.
He gave fully.
Not transactionally. Not conditionally. Completely.
“For God so loved… that he gave.”
That’s the pattern.
The Kind of Love That Lasts
At the center of all this is a better vision of love.
Not a love that takes.
Not a love that consumes.
Not a love that fades when feelings change.
But a love that gives.
A love that stays.
A love that grows.
A love that reflects something bigger than itself.
That’s what sex was meant to point to. Not just desire, but covenant. Not just connection, but commitment.
Something strong enough to carry a lifetime.
The Final Word
We’re still in the middle of the story.
“It is finished” has already been spoken.
“It is done” is still coming.
So we live now with clarity about who we are.
You are not your past.
You are not your worst decision.
You are not your hidden struggle.
You are his.
And that changes everything.
There’s a line from the Song of Songs that captures it simply:
“I am my beloved’s, and he is mine.”
That’s the deepest truth about you if you belong to Christ.
And it’s the kind of love that doesn’t just forgive.
It restores.
It rebuilds.
It makes you whole again.