This morning, we begin a new series called Spiritual Habits, where we will go deeper into what it means to be temples of the Holy Spirit. To start, picture an athlete who signs up for a marathon but never trains. They buy the best shoes, read books on running, and even watch others compete, but they never actually step on the track. It doesn’t make sense, does it?

Yet so often, that’s how people treat the Christian life. We believe in Jesus, we pray here and there, maybe even attend church regularly, but we don’t always discipline ourselves to grow in godliness. And yet, the Holy Spirit reminds us:

“Train yourself to be godly. For physical training is of some value, but godliness has value for all things, holding promise for both the present life and the life to come” (1 Timothy 4:7–8).

And so, just like an athlete can’t succeed without training, no believer can thrive without spiritual discipline. And in this series, we’re going to learn what it means to train—not for an earthly race that fades, but for a strong, flourishing life with God that makes an eternal impact.

Today, we’re turning to Romans chapter 8, where the Spirit of God calls us beyond surface-level Christianity into a life of real depth and transformation. He calls us to deal radically with our sinful nature and to put to death the deeds of the body. Let’s read together beginning in verse twelve:

“Therefore, brothers, we have an obligation—but it is not to the sinful nature, to live according to it. For if you live according to the sinful nature, you will die; but if by the Spirit you put to death the misdeeds of the body, you will live, because those who are led by the Spirit of God are sons of God” (Romans 8:12–14).

This passage makes it clear that we have a choice to make. We are no longer bound to follow the pull of our sinful nature, but we are called to walk in the power of the Holy Spirit. And so, this morning we’re going to learn what it truly means to put to death the deeds of the sinful nature, how to walk it out daily, and how to stay strong until we cross the finish line.

First, notice who Paul is addressing. He says, “Brothers, we have an obligation” (Romans 8:12).

And so, he is speaking directly to believers, brothers and sisters, the church, you and me. In other words, this word is not for the lost, but for the saved. That means the warning that follows is not for the world; it is for us.

“For if you live according to the sinful nature, you will die” (Romans 8:13).

Now, that is a sobering statement, isn’t it? To the church, he warns: if you return to living according to the sinful nature, the result is death. And so, it is possible to drift away, to turn back, and to let sin creep in until it hardens your heart and drags you into destruction.

In other words, the Bible tells us:

“If we deliberately keep on sinning after we have received the knowledge of the truth, no sacrifice for sins is left, but only a fearful expectation of judgment and of raging fire that will consume the enemies of God” (Hebrews 10:26–27).

This is important; this is no trivial matter, because it is possible to exercise our free will and return to death after having received the knowledge of the truth.

Now, I am not sharing this with you to make you fearful, but to wake you up and stir you to action. We are living in a time of great falling away. People who once walked with the Lord are turning back. Some who first served the Lord alongside me are no longer serving Him today. And it grieves my heart to see people I once knew drift away and return to the world.

This warning is real. Some people teach a false sense of security, once saved always saved, but the Bible warns repeatedly that we can’t live according to the sinful nature, letting our flesh rule over us, because our name will be blotted out of the book of life, and so the end of that road is death.

However, the good news is that Paul also shows us another way.

“If by the Spirit you put to death the misdeeds of the body, you will live” (Romans 8:13).

That means we have a responsibility. The Bible teaches that genuine faith will always produce obedience and good works as evidence. And so, we are called not to live according to the sinful nature but to put its misdeeds to death, not letting sin reign in our mortal bodies (Romans 6:12).

In other words, sin wants to rule over us, but we cannot let it. We must resist it. We must reject it. And put to death, whatever belongs to our earthly nature (Colossians 3:5). But this doesn’t happen automatically. It is a daily choice.

Every day we must say no to the flesh and yes to the Spirit. Every day we must take up our cross and choose to follow Jesus. For he said, “If anyone would come after me, he must deny himself and take up his cross daily and follow me” (Luke 9:23).

And so, how do we know if we are truly alive in the Spirit?

Well, there are many signs. First, when you were saved, God gave you a hunger for His Word. The Bible says,

“Like newborn babies, crave pure spiritual milk, so that by it you may grow up in your salvation” (1 Peter 2:2).

In other words, hunger is a sign of life because when a baby loses its appetite, something is seriously wrong. In the same way, when a believer loses their hunger for the word of God, it means something is spiritually wrong.

Second, there is faith, because from the moment you were saved, you knew in your heart that Jesus is alive. No one had to convince you. And so, when you confessed with your mouth, ‘Jesus is Lord,’ and believed in your heart that God raised him from the dead, you were saved (Romans 10:9).

That faith was born in you the moment you believed and experienced new life in Christ.

Third, there is a supernatural love because from the very beginning, the Spirit of God placed in you a love for Jesus—a love for someone you have never seen with your eyes. And that is a miracle of grace because even though you have not seen him, you love him (1 Peter 1:8).

So our calling is clear. We must guard our hunger, hold fast to our faith, and keep our love for Jesus burning strong. Therefore, we cannot feed the flesh. We cannot allow sin to rule. We cannot drift away. Instead, every day we must choose to put to death the misdeeds of the body and live by the Spirit.

And here’s the good news: this is not something that we have to do on our own, because God sent us the Helper. Paul says in verse thirteen, “if by the Spirit,” not your own willpower, not by your own strength, or by your own determination (Romans 8:13).

He says, “by the Spirit,” and the Scriptures confirm this saying, “Live by the Spirit, and you will not gratify the desires of the sinful nature” (Galatians 5:16).

This is the good news, maybe the best news ever, because we are not left to fight the flesh on our own. The Holy Spirit comes to be our Helper. Jesus called Him the Comforter, the Counselor, the One who comes alongside us. And so, the Holy Spirit is the power that enables us to walk in victory. Without him, we can’t do it, but with him, we cannot fail because nothing is impossible with God.

That’s why the Bible tells us, “Clothe yourselves with the Lord Jesus Christ” (Romans 13:14). And we do that by surrendering our lives completely to him. Each morning, we come before him and say, “Lord, I give you my life again. I surrender my heart, my mind, and my will to you.” That is how we put on the Lord Jesus Christ and walk in the Spirit.

Once we have put him on, the Spirit gives us power to “have nothing to do with the fruitless deeds of darkness” (Ephesians 5:11).

That is our obligation, but we can only fulfill it through the Spirit. On our own we are weak, but the Spirit makes us strong. And so, “Since we live by the Spirit, let us keep in step with the Spirit” (Galatians 5:25).

That’s why we should be praying every day, “Holy Spirit, help me to live for Jesus. Help me to walk holy. Help me to yield my life completely to him.” And when we do, he does. He enables us, but we must still obey. He empowers us, but we must still choose. It is our responsibility to act, but it is His power that makes it possible.

Therefore, the Bible says:

“Let us purify ourselves from everything that contaminates body and spirit, perfecting holiness out of reverence for God” (2 Corinthians 7:1).

We purify ourselves, but we do it with the strength and grace the Holy Spirit provides. He gives us the strength to put to death the deeds of the sinful nature. He empowers us to live holy lives. He keeps the flame alive in us even when storms rage all around. All we must do is yield, surrender, and walk in step with Him.

And so, the promises that when we live in obedience, yielding to the Spirit, and dealing with the sinful nature, “you will live” (Romans 8:13).

This is more than just breathing air and existing on this earth. This is the life of God flowing within you. Jesus said,

“I have come that they may have life, and have it to the full” (John 10:10).

That is the abundant life of the Spirit. It is eternal life that begins now and stretches into eternity. It is God’s purpose to conform us “to the likeness of his Son” (Romans 8:29). And so, day by day, as we walk with Him, we are being transformed into his likeness with ever-increasing glory (2 Corinthians 3:18).

And so, to walk in the Spirit, to live in holiness, is the only path to heaven. The prophet Isaiah said,

“The unclean will not journey on it; it will be for those who walk in that Way” (Isaiah 35:8).

This is the promise—you will live. You will walk in His presence now, and you will live with Him forever in eternity.

But on the other hand, the warning is real: if you live according to the flesh, you will die.

But the promise is just as real: if by the Spirit you put to death the deeds of the body, you will live.

Not just survive. Not just get by. You will live in the power of the Spirit, live in the joy of the Lord, live in the peace that surpasses all understanding, and live in the hope of eternal glory.

This is the promise of God to every believer who surrenders and yields to the Spirit—you will live!

But now that we’ve examined this passage, we must also pay close attention to the warnings and encouragements found throughout the Scriptures. Because the Bible tells us,

“The one who sows to please his sinful nature, from that nature will reap destruction; the one who sows to please the Spirit, from the Spirit will reap eternal life” (Galatians 6:8).

In other words, the reason so many return to their old sinful and rebellious ways is simple—they begin feeding the flesh again. They let in the pollution of the world. They watch what is impure and unholy, listening to words that are corrupt, and surrounding themselves with influences that weaken their walk. When you feed the flesh, you reap destruction, but when you sow to the Spirit, you reap eternal life.

That’s why the Bible tells us: “Do not conform any longer to the pattern of this world, but be transformed by the renewing of your mind” (Romans 12:2).

You and I cannot afford to think like the world or live like the world, because the world’s values, priorities, and ways of living are vain, temporary, and empty, but your life, your identity, and your allegiance are anchored in heaven. The Scriptures declare: “Our citizenship is in heaven” (Philippians 3:20).

That’s why Proverbs instructs us, “Above all else, guard your heart, for it is the wellspring of life” (Proverbs 4:23).

Everything in your walk with God flows from the condition of your heart. That is why the enemy works so hard to pollute it, distract it, and weigh it down with the cares of this life. Jesus warned us to be careful about who and what we allow into our lives. It only takes one wrong relationship, one wrong influence, or one wrong friend to tear down what God has been building in you for years (Ecclesiastes 9:18).

This is why we must stay surrounded by people who strengthen us, not weaken us—people who feed our faith, not dragging us down to their level.

And so, let me encourage you to stay in the Word, staying in prayer, staying filled with the Spirit, and staying separate from the pollution of this world. Don’t let the enemy steal what God has planted in you. If you guard your heart, feed the Spirit, and walk in holiness, the promise of God is clear —you will live!

Now let’s move into the practical application of what we have learned. Paul has shown us the warning, the obligation, the Helper, and the promise, but now we must answer the question,

“How do we live this out every single day?”

First, it begins with a prayer that we must make our own. A prayer like David prayed,

“Create in me a pure heart, O God, and renew a steadfast spirit within me. Do not cast me from your presence or take your Holy Spirit from me. Restore to me the joy of your salvation and grant me a willing spirit, to sustain me” (Psalm 51:10–12).

Every day we need to ask God to keep our hearts pure, our spirits steadfast, and our walk holy. So each morning we can pray, “Lord, sin shall not be my master, don’t let sin rule my life today, but by your Spirit, keep me free from sin” (Romans 6:14).

Second, stay in the Word of God, because the Scriptures are your lifeline.

“The law of the Lord is perfect, reviving the soul” (Psalm 19:7).

When you read the Bible deeply and daily, it renews your mind and keeps your spirit alive. Without the Word, your hunger fades, your faith weakens, and your love grows cold. But with the Word alive in you, the Spirit keeps your heart burning.

Third, starve the flesh. Don’t feed it. The Bible says, “Put to death, therefore, whatever belongs to your earthly nature” (Colossians 3:5).

“Don’t even think about how to gratify the desires of the sinful nature” (Romans 13:14).

You starve the flesh by refusing to entertain it, refusing to make provision for it, refusing to give it any room in your life.

Fourth, you feed the Spirit. You feed what you want to grow. And so, you fill your heart and mind with what is holy and pure. The Bible says,

“Whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or praiseworthy—think about such things” (Philippians 4:8).

And when you meditate on these things, you find your spirit grows strong because your faith is fed.

And finally, commit yourself to finishing well. Don’t just start the race, but finish it. Paul testified saying,

“I have fought the good fight, I have finished the race, I have kept the faith” (2 Timothy 4:7).

That must be our goal. Not just to begin strong, but to end strong. Not just to taste of the Spirit, but to walk with Him all the way to the finish line. If you do these things, you will walk in the Spirit, live in His power, and finish your race in victory.

Now, as we close, we come to the call to commitment. Paul’s words in Romans 8 are not just truths to be studied; they are an invitation to make a decision. This is where the Word meets your will. This is where you decide there is no turning back.

“Therefore, brothers, we have an obligation—but it is not to the sinful nature, to live according to it” (Romans 8:12).

Our obligation is to God. He purchased us with his blood, filled us with his Spirit, and so we owe him our very lives. That means there is no going back, no return to the old ways, like the disciples said to Jesus,

“Lord, to whom shall we go? You have the words of eternal life” (John 6:67–68).

That must be our response today: to whom shall we go? There is no turning back. The world has nothing for us. Only Jesus has the words of life.

So here is the commitment:

Even if no one else goes with me, I will follow. Even if persecution comes, I will not deny Him. Even if trials and temptations surround me,

“I press on toward the goal to win the prize for which God has called me heavenward in Christ Jesus” (Philippians 3:14).

And here is the prayer: “Holy Spirit, help me to finish the race. Help me to finish strong. Help me to keep my eyes on Jesus until the very end.”

That is our calling, and that must be our commitment.

Graphics, notes, and commentary from LifeChurch, Ministry Pass, PC Study Bible, Preaching Library, and Sermon Central. Scripture from the New International Version unless otherwise noted.