Sin will never make you happy.

On the bark of every tree in God's garden are carved the words: "But if the seed dies, it brings forth much fruit" (John 12:24). And three words are engraved on the heart of every Christian: "For ye are dead" (Col. 3:3). The sincere confession of every believer is: "I am crucified with Christ" (Gal. 2:19).

But what does that mean? Who died when I became a Christian? The answer is simple: my «body» died. «And they that are Christ’s have crucified their own body» (Gal. 5:24). But what is «the body»? It is not my skin or my physical covering. The body can be an instrument of righteousness (Rom. 6:13). So we are not talking about the physical form.

What, then, does «the flesh» mean? The answer is found in the works of the flesh. «The works of the flesh are manifest»—such things as idolatry, strife, anger, and envy (Gal. 5:19–21). These are attitudes and inner sinful desires, not just immoral acts.

«"The stakes in the battle against sin are extremely high. This is not just a game of war—the outcome of this battle will determine whether we go to heaven or hell.".

The closest we can get to a biblical definition of the «flesh» is found in Romans 8:7–8: «Because the carnal mind is enmity against God: for it is not subject to the law of God, neither indeed can be. And they that are in the flesh cannot please God.» The flesh is the old nature with which I once rebelled against God. In the flesh I was hostile and disobedient. I hated to admit my sinfulness, I denied that my greatest need was for the Great Physician to heal me. I relied on my own wisdom, not on God’s. Therefore, nothing I did in the flesh could please God, for «without faith it is impossible to please God» (Heb. 11:6). The flesh is incapable of acting by faith.

So, the «flesh» is the old nature that relied on itself and had no faith. It died when God saved me. The Lord stopped the flow of blood in my old, unbelieving heart of stone. And when it died, He took it and gave me a new heart (Ezekiel 36:26).

What is the difference between a new heart that lives and an old heart that has died? The answer is found in Galatians 2:19–20: «I have been crucified with Christ… And the life which I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me.» The old heart trusted only in itself, but the new heart daily relies on Christ.

Fight sin by trusting in Jesus

How can those who are dead to sin fight against it? They fight by trusting in the Son of God. Christians are already dead to Satan’s deceptions, to lies like, «You will be happier if you trust your own ideas about happiness instead of trusting the counsel and promises of Christ.» They fight against Satan by being convinced that the way and promises of Christ are far better than any promises of the enemy.

This fight against sin is called «the good fight of faith.» (1 Tim. 6:12; 2 Tim. 4:7) Victories in this fight are «the work of faith.» (1 Thess. 1:3; 2 Thess. 1:11) In this war, Christians «are sanctified through faith in Jesus.» (Acts 26:18).

«"The power of any temptation lies in the illusion that it will make you happier. But sin will never make you happy.".

Let us consider this «fight of faith.» This is not a game of rubber bullets. Eternity is at stake. Romans 8:13 is a key verse: «For if you live according to the flesh, you will die; but if by the Spirit you put to death the deeds of the body, you will live.» This is addressed to those who call themselves Christians, and the point is that our eternal life depends on our struggle against sin. But this does not mean that we gain eternal life by mortifying sin. No, the struggle is waged by «the Holy Spirit,» and He alone deserves all the glory, not us.

Romans 8:13 also does not mean that we should struggle with anxiety and uncertainty about the outcome. On the contrary, in this struggle we are confident that «he who began a good work in you will complete it until the day of Jesus Christ» (Phil. 1:6). And this verse does not say that we must already be perfect in our victory over sin. Paul renounces any claim to perfection: «Not that I have already obtained it or am already perfect, but I press on to take hold of that for which Christ Jesus has taken hold of me» (Phil. 3:12).

The War That God Requires

Romans 8:13 is not about sinlessness, but about a deadly struggle against sin. It is absolutely necessary for the Christian life. If we do not fight this battle, we are not demonstrating that our flesh (the old nature) is crucified. And if the flesh is not crucified, we are none of Christ’s (Gal. 5:24). The stakes in this battle are extremely high. This is not a war game—the outcome of this battle determines whether we go to heaven or hell.

How then do people who are «dead to sin» «mortify the deeds of the body»? We have already answered, «Through faith!» But what does this mean in practice? How exactly do we fight sin with faith?

Let us imagine that I am tempted by lust. Suddenly some sexual thought arises in my mind, urging me to give in to it. This temptation gains strength, convincing me that I will be happier if I follow it. The power of any temptation lies in the promise that it will make us happier. No one sins out of a sense of duty if they really want to do what is right.

«"Faith is not just the belief that Christ died for our sins, but also the confidence that He is far better than sin.".

So what should I do? Some will say, «Remember God’s commandment to be holy (1 Pet. 1:16) and by an effort of the will fulfill it, for He is a Holy God!» But this advice lacks one important element: faith. Many people try to improve themselves morally, but they cannot say, «The life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me» (Gal. 2:20). Many try to love, not realizing that the most important thing is «faith working through love» (Gal. 5:6). The struggle against lust (or greed, fear, or some other temptation) is a struggle of faith. Otherwise, the result will be nothing but legalism.

Fighting Sin with the Spirit

When temptation provokes sinful desires, Romans 8:13 says, «If by the Spirit you put to death the deeds of the body, you will live.» By the Spirit! What does that mean? Of all the weapons God gives us to fight Satan, only one is designed for destruction—the sword. It is the sword of the Spirit (Eph. 6:17). So when Paul says, «Put to death sin by the Spirit,» I understand it to mean, «Rely on the Spirit, especially His sword.».

And what is the sword of the Spirit? It is the Word of God (Eph. 6:17). And that’s where faith comes in. «So then faith comes by hearing, and hearing by the word of Christ» (Rom. 10:17). The Word of God cuts through the fog of satanic lies and shows me where true and lasting happiness lies. So the Word helps me to stop trusting in sin’s potential to make me happy and encourages me to rely on God’s promise of joy (Ps. 16:11).

I wonder how many believers today understand that faith is not just the belief that Christ died for our sins. Faith is also the assurance that His way is better than sin. His will is wiser, His help is more reliable, His promises are more precious, and His reward is more satisfying. Faith begins with a look back to the cross, but it lives with a look forward to God’s promises. Abraham «was strong in faith… and was fully convinced that what he had promised he was able to do» (Rom. 4:20–21). «Faith is the substance of things hoped for, the evidence of things not seen» (Heb. 11:1). Faith is the assurance of things hoped for.

When faith has the upper hand in my heart, I am satisfied with Christ and His promises. This is what Jesus meant when He said, «He who believes in Me will never thirst» (John 6:35). If my longing for joy, meaning, and passion is satisfied by the presence and promises of Christ, then the power of sin is broken. We will not be tempted by a piece of sandwich when a juicy steak is grilling in front of us.

Pleasure kills sin

«"If my thirst for joy, meaning, and passion is satisfied by Jesus, the power of sin is broken.".

The struggle of faith is the struggle to remain pleased with God. «By faith Moses … [rejected] the temporary pleasures of sin … because he looked intently to the reward» (Heb. 11:24–26). Faith is not satisfied with «temporary pleasures.» It seeks true joy. And the Word of God says, «In your presence is fullness of joy; at your right hand are pleasures forevermore» (Ps. 16:11). Therefore, faith does not stray from the path of sin. It does not give up so easily in its search for maximum joy.

The role of God’s Word is to feed the thirst for faith in God. When this happens, my heart is weaned from the deceptive allure of false desires. At first, these desires may seem so great that I will lose out on true satisfaction if I follow the path of purity. But then I take up the sword of the Spirit and begin to fight.

I read that it is better to pluck out an eye than to give in to a false desire (Matt. 5:29). I read that if I think about pure, lovely, and good things, the peace of God will be with me (Phil. 4:7–8). I read that the mind on the flesh leads to death, but the mind on the Spirit brings life and peace (Rom. 8:6). And when I pray that my faith will find satisfaction in God’s life and peace, the sword of the Spirit peels away the sugar coating from the poison of false desires. I see them for what they are. And through God’s grace, their appeal is destroyed.

Faith that moves forward

This is how those who have died to sin fight. This is the essence of Christianity. We have died to sin in the sense that the old unbelieving self (the flesh) has died. A new creation has taken its place. What makes us new? Faith. And not just faith that looks back to the death of Jesus, but faith that looks forward to his promises. It is not just confidence in what he has done, but also a satisfaction in what he will do in the future.

With eternity at stake, we are fighting a battle of faith. Our chief enemy is the lie that sin will make us happier in the future. Our chief weapon is the truth that God will give us true happiness in the future. Faith is the victory that overcomes lies because faith finds satisfaction in God.

«"The challenge is not just to do what God says because He is God, but to desire what God says because He is Good.".

Our challenge, then, is not only to keep God’s commandments because He is God, but to desire to keep them because He is Good. The challenge is not only to seek righteousness but to choose it as something better. Every morning, as we rise, we should prayerfully meditate on the Scriptures until we experience joy and peace in faith in «the exceeding great and precious promises of God» (Rom. 15:13; 2 Pet. 1:4). And with this joy before us, God’s commandments will not be burdensome (1 John 5:3), and the temptations of sin will seem too fleeting and superficial to tempt us.