Why the Flesh Fights the Spirit: Understanding the Struggle With Sin Every Christian Feels
Every believer knows the feeling. You wake up wanting to honor God, but as the day unfolds, you find yourself in a struggle with sin you didn’t expect. A thought you didn’t invite. A reaction you didn’t want. A temptation that slips in through a side door you never meant to leave open.
I’ve lived long enough to know this isn’t an occasional skirmish. It’s a war inside the believer, and Scripture doesn’t pretend otherwise. Paul doesn’t soften it. He speaks plainly:
“For the flesh desires what is contrary to the Spirit, and the Spirit what is contrary to the flesh. They are in conflict with each other…” (Gal. 5:17)
If you’ve read any of my sin-centered articles at waltroderick.com, you already know this struggle with sin is deeper and more persistent than many Christians want to admit. Grace doesn’t erase the war. Grace anchors you while you walk through it.
This is for anyone who has ever asked, “Why is this struggle with sin still so hard? Shouldn’t I be past this by now?”
The Battle Didn’t Start With You — It Started the Moment You Were Born Again
Before new birth, the struggle with sin didn’t exist in you. There was no internal conflict because the Spirit wasn’t present. Sin wasn’t resisting you; it was shaping you. You weren’t at war — you were in agreement.
But the day God made you alive in Christ, two opposing natures began to pull in opposite directions.
Paul frames it in Romans 7:
“I delight in the law of God in my inner being, but I see another law waging war…”
If sin feels louder after conversion, it’s because you’re alive now. Only living believers feel the tension — the struggle with sin, yes, but also the new desires the Spirit brings.
The Flesh Isn’t Your Body — It’s the Old You Trying to Survive
When people hear “flesh,” they often think of physical impulses. But biblically, the flesh is broader than just appetite. It’s everything in you that belonged to the old nature — your old instincts, old habits, old cravings, and old reactions – lust, anger, covetousness, gluttony – and everything that is against godliness.
In Why Do I Keep Sinning?, I wrote about how shocked Christians are when old desires return. The surprise comes from misunderstanding the flesh. Conversion breaks the power of sin, but not the presence of it. The flesh wants to keep its territory.
That resistance is part of the ongoing spiritual conflict every believer hands over to God again and again.
The Spirit Doesn’t Fight You — He Fights For You
The struggle with sin sometimes feels like two equal forces battling inside you. But the Spirit isn’t wrestling you. He’s opposing the flesh to form Christ in you.
This is why Galatians 5 points to the fruit of the Spirit right alongside the conflict:
- Love
- Joy
- Peace
- Patience
- Kindness
- Goodness
- Faithfulness
- Gentleness
- Self-control
If you’ve read What Should I Do After I Sin Again?, you know this:
Your struggle with sin isn’t evidence of God’s absence. It’s evidence of His work.
Why the Battle Feels Worse When You’re Trying to Live Holy
Most Christians assume that when they get serious about holiness, temptation will fade. But what often happens is the opposite.
Here’s why the inner war intensifies:
- Awareness sharpens before obedience strengthens.
You’re seeing more clearly now. - The flesh reacts when threatened.
The old self fights back when it loses influence. - Obedience exposes deeper loyalties.
The closer you walk with Christ, the clearer the cracks become.
In Is Grace a License to Sin? I said, “When grace becomes real, sin becomes serious.”
That seriousness magnifies the fight against the flesh.
You’re Not Failing — You’re Being Formed
Many assume the presence of conflict means they’re failing spiritually. Biblically, the presence of conflict means you’re being formed.
Romans 8 reminds us:
“Those who belong to Christ Jesus have crucified the flesh with its passions and desires.”
Crucifixion is slow. Crucifixion is painful. Crucifixion is certain.
And the struggle with sin is part of that crucifying process.
In Why Do I Keep Sinning?, I compared sanctification more to a battlefield than a staircase. If you feel the smoke and noise and confusion — you’re in the real fight.
The Struggle Doesn’t Prove Weakness — It Proves Ownership
The flesh loves to whisper:
“If you were really saved, you wouldn’t still face this.”
But the truth is far different:
- Only a regenerate heart grieves sin.
- Only a Spirit-born heart feels the war within.
- Only a child of God feels torn between what they want now and what they want most.
If there were no conflict at all, that would be the troubling sign.
So Why Does God Let the Battle Continue?
At 70, I’ve seen what this long inner battle Christians face does to the soul:
- It makes Christ precious.
You don’t love grace until you need it. - It deepens repentance.
Not a single apology — but a lifetime of turning. - It creates compassion.
People who have faced themselves are patient with others. - It anchors your hope.
The fight reminds you that this world isn’t home.
God doesn’t allow the conflict because He’s distant.
He allows it because He’s committed — to you, to your growth, and to His glory in your life.
How to Fight When You’re Tired of Fighting
Scripture gives concrete help for believers worn down by the struggle with sin:
- Starve the flesh.
What you feed grows. - Saturate your mind with truth.
Romans 12:2 is transformation, not behavior management. - Confess quickly.
Hidden sin thrives. Exposed sin dies. - Walk with others.
Isolation feeds temptation. - Remember who holds you.
This isn’t a battle you win by strength.
The Day the Struggle Ends
One day, the struggle with sin will end. Not because you overcame the flesh through sheer effort, but because Christ will complete what He began. The flesh dies. The Spirit remains. Your desires align with His perfectly.
Until then, the conflict is a sign of life — not defeat.
If This Struggle Is Real for You, Don’t Walk It Alone
If any of this describes your life, stay with the conversation through the rest of the sin series on waltroderick.com:
- Why Do I Keep Sinning?
- Is Grace a License to Sin?
- What Should I Do After I Sin Again?
- Why Easy Believism Isn’t the Same as Saving Faith
Each one speaks into the same long, honest struggle with sin every believer knows.
Walt Roderick is a Christian writer who cares more about biblical clarity than online applause. He writes to strengthen believers and confront spiritual drift.
