2026 Stronghold Sermon Series #4: The Flesh Vs. The Spirit

by Mike Costanzo | Aug 12, 2026 | Speaking, Stronghold 2026

 

“For we know that the law is spiritual, but I am of the flesh, sold under sin. For I do not understand my own actions. For I do not do what I want, but I do the very thing I hate. Now if I do what I do not want, I agree with the law, that it is good. So now it is no longer I who do it, but sin that dwells within me. For I know that nothing good dwells in me, that is, in my flesh. For I have the desire to do what is right, but not the ability to carry it out. For I do not do the good I want, but the evil I do not want is what I keep on doing. Now if I do what I do not want, it is no longer I who do it, but sin that dwells within me.

So I find it to be a law that when I want to do right, evil lies close at hand. For I delight in the law of God, in my inner being, but I see in my members another law waging war against the law of my mind and making me captive to the law of sin that dwells in my members.” (Romans 7:14-23)

A Split Spirituality?

“Please allow me to introduce me,
Half of me slave, the other half free
Righteous and sinful both at the same time
Iniquity and purity fill up the same mind
And out of the same mouth the holy and profane
I curse all my brothers then I bless Christ’s name
I hang in the balance but still I’m secure
I’m leaning towards evil but striving to be pure

I’m curious. How many of you can relate to the words I just spoke? I know I can. They’re not my words; they’re from a 27-year old OC Supertones album. But I think they perfectly encapsulate the kind of internal conflict that Christians often find themselves facing.

And yet, for many of us, this kind of talk is taboo in our Christian circles. I know for a fact that there are Christians out there who would condemn this kind of testimony as blasphemous. They would say that there is no conflict like this in a true Christian believer, because after all Christ is not divided, and if we are one with Him then we can have no internal conflict. I even once spoke to a man who was convinced that he no longer willingly committed any sin at all simply because he was a Christian. He saw no conflict within himself, and could not understand how a Christian could be so divided within himself.

That’s why I’m so grateful that Paul wrote Romans 7. Without Romans 7, I would have probably walked away from the faith, because I’m not the kind of person who does well pretending to be OK when I’m not OK. I can’t put on a happy face and wave to everybody at church and say, “Oh yes, I’m doing fabulous, no deep and abiding struggles with indwelling sin here!” I don’t fit in well with super church-y people who pretend they have no internal conflict, who don’t seem to strive and wrestle deep inside their souls like I do. And without a passage like this, I would have come to the conclusion that I was alone in this conflict.

But I’m not alone! And neither are you. We’re in good company, you and I. If the Apostle Paul could write Romans 7—the Apostle Paul!—then there is hope for us all. So let’s get into it, shall we?

The Flesh Vs The Spirit

The first thing we see in verse 14 is this phrase: “We know that the law is spiritual, but I am of the flesh.” What does the Apostle Paul mean by this?

The word “flesh” in Greek—which is pronounced sarks (σάρξ) if anyone cares—can have two meanings. First and most obviously, it can refer to the stuff that our physical bodies are made of. This stuff. That’s what the Apostle John meant when he says that “the Word became flesh and dwelt among us.” And unlike what some other religions might tell you, your flesh—that is, your earthly body—is not morally evil in and of itself. Otherwise, how could Jesus have taken on an earthly human body and still remained sinless? No, our bodies are an incredible gift of grace from the Lord. Without them, we wouldn’t be human. So thank the Lord for your body, for you are fearfully and wonderfully made!

But the word σάρξ (or “flesh”) has another meaning, and this one is not a blessing, but rather a curse. It has to do with our sinful nature, that part of our souls that is anti-God and hell-bent on doing what is wrong. Now if there is anyone here who is from the Walt Disney school of anthropology and the humanities, you are probably shocked and appalled that I would dare to insinuate such a thing. After all, aren’t all people basically good deep down inside? But if there are any of you who come from the school of hard knocks like I do, you know that the sinful nature is real. All of us are inherently selfish, greedy, dishonest swindlers who will do anything to get ahead. We don’t have to be taught how to lie, or how to steal, or how to be rude. That comes naturally. And without the restraining grace of God’s spirit who instructs us how to love each other, how to tell the truth, and how to live as decent human beings, we would descend into feral creatures of darkness in a surprisingly short amount of time.

And God knows this! The New Testament is full of passages that express this tension between what is spiritual and what is of the flesh—that is, our sinful nature. Galatians 5:17 says it this way:

“For the desires of the flesh are against the Spirit, and the desires of the Spirit are against the flesh, for these are opposed to each other, to keep you from doing the things you want to do.”

And Romans 8:5-8 says it like this:

“For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit set their minds on the things of the Spirit. For to set the mind on the flesh is death, but to set the mind on the Spirit is life and peace. For the mind that is set on the flesh is hostile to God, for it does not submit to God’s law; indeed, it cannot. Those who are in the flesh cannot please God.”

You can see the tension there clear as day, can’t you? The reason our flesh is sinful is because it is anti-God. It will always resist God because that’s what it is. Whatever God loves, it hates. Whatever God delights in, it despises. Whatever God wants, it resists. Remember how we talked about Adam and Eve wanting not just to be like God, but to be God? They wanted to supplant Him, to depose Him from His heavenly throne and reign in His place. And that’s what our flesh wants. That’s why Paul says the flesh is hostile to God. That’s why those who are in the flesh—that is, those who do not have Christ as their Savior—cannot please God.

Let’s get back to Romans 7. Paul says, For I do not do what I want, but I do the very thing I hate. What does he mean here? He’s talking about the struggle between his flesh and the Spirit of God, and the battleground that they’re fighting over—the contested warzone upon which the conflict rages—is his own soul. Paul says clearly that he has the desire to do what is right—in fact, in verse 21 he goes on to say he delight[s] in the law of God, in [his] inner being. So his faith is real! He really, truly loves God and wants to serve Him.

And yet, he can’t. Why? Because he keeps on sinning! Every single time he wants to do good, sin is right there, waiting for him. It’s like clockwork. In fact, he even calls it a “law,” a fundamental truth about the universe that describes how things work. And this law of sin goes as follows:

IF you desire to do what is right, THEN evil lies close at hand. IF your spirit loves God and wants to serve Him, THEN your flesh will tempt you to serve yourself instead. IF you try to live at peace with God, THEN sin will wage war against you and try to take you captive.

Yikes! That’s intense, right? But it’s true! I can attest to the veracity of this law of sin, how it wages war against the law of my mind and makes my heart a bloody battleground. No wonder Paul says, I do not understand my own actions. It’s hard to understand yourself when you’ve got two opposing forces constantly pulling in opposite directions inside you. It can make you feel crazy. St. Augustine, when he was young, gives us a perfect example of this dichotomy when prayed, “God, give me purity and self-control—but not yet.” That’s crazy, right? There’s an even better word for it—human.

Put Off vs Put On

So how do we go about this inner battle that won’t just result in us spinning our wheels and burning ourselves out? The Apostle Paul tells us in Ephesians 4:17-24:

Now this I say and testify in the Lord, that you must no longer walk as the Gentiles do, in the futility of their minds. They are darkened in their understanding, alienated from the life of God because of the ignorance that is in them, due to their hardness of heart. They have become callous and have given themselves up to sensuality, greedy to practice every kind of impurity. But that is not the way you learned Christ!—assuming that you have heard about him and were taught in him, as the truth is in Jesus, to put off your old self, which belongs to your former manner of life and is corrupt through deceitful desires, and to be renewed in the spirit of your minds, and to put on the new self, created after the likeness of God in true righteousness and holiness.

He begins this section with a clear command—don’t walk as the Gentiles do. All that sensuality, all that impurity, all that darkness and futility and ignorance—don’t live like that. If you are a Christian, then you can’t live like that, because your life is hidden with Christ in God (Colossians 3:3) and is not wrapped up in the pleasures of this world. As the Apostle John says, in 1John 3:

“Everyone who makes a practice of sinning also practices lawlessness… No one born of God makes a practice of sinning, for God’s seed abides in him; and he cannot keep on sinning, because he has been born of God.”

So what are we to do instead? Let’s look back at Ephesians, Chapter 4, verses 21 and 22:

“…assuming that you have heard about him and were taught in him, as the truth is in Jesus, to put off your old self, which belongs to your former manner of life and is corrupt through deceitful desires…”

We are given a command here, namely, to “put off our old selves.” The word “selves” in the Greek is literally the word for “man,” which is why some translations say, “put off the old man.” In other words, the person you used to be before you became a Christian. Remember that guy? His name is the flesh. He hates God, cannot submit to God, and wants you to dive head first into sin.

What are we to do with him? “Put him off.” The word here has the sense of taking off a garment and laying it aside. Have you ever been sprayed by a skunk? Have you ever known anybody that was? It’s nasty, nasty stuff! Now imagine someone walked into this room wearing a shirt that had been sprayed by a skunk. We would all be like, “Dude! You gotta change your shirt, bro!” Why? Because it’s filthy and disgusting! And when you change your shirt, don’t keep it with you. Lay it aside. Throw that thing in the laundry. Throw it in the garbage if you have to!

That’s exactly the idea here. Your old self—that is, your old man, the flesh—belongs to your former manner of life and is corrupt through deceitful desires. In other words, it’s nasty. Filthy, Disgusting. It’s like a t-shirt that’s been marinating in lies and sinfulness and wickedness. And the longer you live, the nastier and grosser your garment gets. Some of you may not have lived long enough to really make some terrible, sinful mistakes, but sooner or later you’ll know what I’m talking about. When Jesus told the crowd in John 8, “Let him who is without sin among you be the first to throw a stone,” there’s a reason the older ones went away first. They knew their garments—in other words, their track records—were filthy.

But we don’t just take it off the old selves and lay them aside, we also put on the new self, created after the likeness of God in true righteousness and holiness. If all you do is try to resist sin by taking off your old self, you won’t have any victory because you’re only focusing on half of what is important. It’s equally important to PUT ON your new self, the self that Jesus died to make possible! You can’t just die to sin, you also have to walk in newness of life. Otherwise, where will your power to do what is right come from? From you? Give me a break. No, from the Holy Spirit! This is why Paul says we must be renewed in the spirit of [our] minds. That’s where the power comes from.

So what does that look like, practically speaking, when you are tempted to sin? Let’s say you’re at home, and somebody takes the last corn dog or sneezes all over the last cookie or whatever. How do you respond? If you’re currently putting on the old man, you’ll likely be subsumed by anger and jealousy and resentment. How dare they! Don’t they know that I wanted that? That was MINE! I’ll make them pay!

Now, let’s put these verses into action. First, we put off the old man. You can literally imagine yourself taking off an invisible outer layer and laying it aside. All that stuff—the rage, the envy, the selfishness and pride—that’s the old me. That’s the me that Christ died to free me from. It’s filthy and disgusting. But that’s not who I am anymore. Then, you can imagine yourself putting on a new invisible layer of clothing, which is the new self. This is who I am. I belong to Christ now. He is what is important to me, not some corndog or cookie or whatever. He wants me to love others, to be selfless, and to treasure Him more than anything, even corndogs and cookies. By preaching truth to yourself and reminding yourself of who you really are, you are putting off the flesh, and putting on your new self.

Now, just do that for the rest of your life and you’ll be fine.

Closing Encouragement

OK, obviously I’m exaggerating. Putting off your old self and putting on your new self is not as easy as it sounds. It’s hard work. Preaching truth to yourself and being renewed in the spirit of your mind is not something you can do fully in 30 seconds on a Saturday. It’s a lifetime commitment, a perpetual struggle that you must commit to if you plan to give your life to Jesus. But it’s worth it.

And the good news is, the battle has already been won! 2 Corinthians 4:16-18 says this:

“So we do not lose heart. Though our outer self is wasting away, our inner self is being renewed day by day. For this light momentary affliction is preparing for us an eternal weight of glory beyond all comparison, as we look not to the things that are seen but to the things that are unseen. For the things that are seen are transient, but the things that are unseen are eternal.”

Now, the phrase “outer self” has to do with our physical bodies as well as the human limits of emotional and mental endurance. The longer we exist in this world, the more of a toll it takes on us. It takes energy to fight the good fight, and if you rely on your own strength, I guarantee it will fail you, because it’s wasting away. But what about your inner self, the new man who is created to be like God in true righteousness and holiness? He (or she) is being renewed day by day. It is God alone who can sustain you and keep you joyful to the end!

And not just that, but our struggles are preparing for us an eternal weight of glory beyond all comparison. In other words, all these temporary conflicts and wars we fight have everlasting purpose and value. They are glorious, meaning not only that they give God glory, but they are also making YOU glorious. Let me say that again: our earthly turmoil is preparing for us an eternal weight of glory beyond all comparison. There is a purpose in all our sufferings. God doesn’t waste even a single tear. “Weeping may tarry for the night, but joy comes with the morning.” (Psalm 30:5) Amen?

But how can we be sure that this will happen? Romans 6:5-11 has the answer:

“For if we have been united with him in a death like his, we shall certainly be united with him in a resurrection like his. We know that our old self was crucified with him in order that the body of sin might be brought to nothing, so that we would no longer be enslaved to sin. For one who has died has been set free from sin. Now if we have died with Christ, we believe that we will also live with him. We know that Christ, being raised from the dead, will never die again; death no longer has dominion over him. For the death he died he died to sin, once for all, but the life he lives he lives to God. So you also must consider yourselves dead to sin and alive to God in Christ Jesus.”

If you are in Christ, then your old self was crucified with him in order that the body of sin might be brought to nothing. What does it mean that your old self was crucified with Christ? It means that your flesh—your sinful nature—has been dealt with on the cross and defeated once and for all. Like Satan, it cannot gain the victory, because Jesus has already triumphed. And while it may thrash around and fight you all the days of your life, it will ultimately come to nothing. A day is coming soon when you will be in the presence of the Lord, and you will be completely sinless and holy. Where will your sinful nature be then? Destroyed. Eradicated. Terminated. And all the ransomed church of God will be saved to sin no more! Amen?

In the meantime, we must consider ourselves dead to sin and alive to God in Christ Jesus. Jesus has died to sin, and so have we. Jesus was raised to life, and so shall we be. All we need to do is live in the light of this reality. In other words, the Bible commands us to be who we are. It doesn’t tell us to be someone we’re not, and it definitely doesn’t want us to be who we USED to be. No, we are to be who we are in Christ. You are more than conquerors, so live like it! You are prophets, priests, and kings in God’s kingdom So live like it! You have been cleansed from your sins! So live like it! You are a beloved child of the King, whose true home is in heaven. So live like it.

“What you have learned and received and heard and seen…—practice these things, and the God of peace will be with you.” (Philippians 4:9)

Let’s pray.

Other Messages In This Series:

Stronghold Logo

0 Comments