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. Wretched man that I am! Who will deliver me from this body of death? Thanks be to God through Jesus Christ our Lord! So then, I myself serve the law of God with my mind, but with my flesh I serve the law of sin. – Romans 7:21-25 ESV Up to this point in his letter, Paul has mentioned six different laws at work in the lives of those to whom he was writing. There was the law of Moses, which God had given to the people of Israel, and which could only expose and condemn sin. There was also law as a principle, apart from the law of Moses, which caused all men to have an awareness of right and wrong. Paul included the law of faith, which is apart from any acts of self-righteousness. There was also the law of the mind, which agrees with the law of Moses, but is incapable of obeying it because of the law of sin. The law of sin, yet another law, is always victorious over the law of the mind. Then finally, there is the law of the Spirit, which provides the believer with victory over the law of sin which resides in his body and allows him to live obediently to the law of Moses.
In verse 21, Paul mentions when he wants to do what is right, in his mind, the temptation to do evil is always right there. He calls this a law. He is most likely referring to the law of the mind, which is aware of God's holy expectations, but always susceptible to the desires of the flesh or the law of sin. He says, “I delight in the law of God (the Mosaic law) in my inner being (in his mind), but he sadly confesses, “I see in my members (his body) 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 7:23 ESV). The dilemma that Paul presents is one that all believers face every day of their lives. We know in our minds what God expects of us and we want to do what is right. But the law of sin exists in our bodies. We have our sin natures that remain alive and active in our earthly bodies. And as Paul says in Galatians, our sin natures do battle daily with the Spirit who lives within us. It is a battle for control.
It is interesting to note that the Greek word Paul uses over and over again for “law” is nomos and, according to Strong's Concordance, it is derived from another Greek word, némō, which means “to parcel out, especially food or grazing to animals.” Nomos came to mean, “anything received by usage, a custom, a law, a command.” So the law of the Spirit requires usage. God has given the Spirit to us to be used, like a shepherd providing food to grazing animals. Unless they eat what is provided, they miss out on the intended benefits. Paul paints a picture of what daily life is like for the believer. We have active sin natures that are opposed to the Spirit's role in our lives. The law of our minds tells us what we need to do but, in our own strength, we lack the moral fortitude to obey. In that sad condition, we are forced to cry out, “Wretched man that I am! Who will deliver me from this body of death?” (Romans 7:24 ESV). The law of the mind is no match for the law of sin. The mind's desire to do what is right cannot stand against the body's desire to sin. Any victories we enjoy will be short-lived. That is why self-righteousness does not work. It's also why we need the law of the Spirit. He is the key to our deliverance from this body of death. And He was provided to us through Jesus Christ. But we must make use of His presence and power. The principle or law of the indwelling Spirit of God is only effective when we submit to His authority in our lives. Which is why Paul reminds us, “So I say, let the Holy Spirit guide your lives. Then you won’t be doing what your sinful nature craves. The sinful nature wants to do evil, which is just the opposite of what the Spirit wants. And the Spirit gives us desires that are the opposite of what the sinful nature desires. These two forces are constantly fighting each other, so you are not free to carry out your good intentions. But when you are directed by the Spirit, you are not under obligation to the law of Moses” (Galatians 6:16-18 NLT).
There are many laws at work. But only one can equip us to live Christ-like lives in the midst of a sinful world and in spite of our indwelling sin natures. It is the law of the Spirit. We must learn to live in obedience to Him. In the very next chapter, Paul tells us we are to “walk not according to the flesh but according to the Spirit” (Romans 8:4 ESV). We are not to live according to the law of Moses, attempting to earn favor with God through our keeping of His holy commands. We are not to live according to the law of the mind, determining to do good, but constantly failing. We are also not to live according to the law of sin, giving in to our fleshly desires. We are to live according to the law of faith, apart from any acts of self-righteousness and we are to live according to the law of the Spirit, relying on His presence and power within us to produce His fruit through us.