Paul shows that while we are free from the law, there remains a true battle with sin that resides within us. The sin nature battles with the redeemed nature. The sin nature is so strong that only the power of Christ can deliver us from it.
This of course pulls the rug out from under the main point made by Paul’s opponents (the competing Jewish “authorities”). They have argued that the law is what brings us to righteousness. Paul’s counter is that the law actually shows us our sin, and it is the power of the Spirit of Jesus that delivers us from the power of sin in our daily walk.
Paul is telling his audience of believers in Rome that, like the widow who is no longer bound by the covenant of marriage to her dead husband, Christian believers are no longer bound to the covenant of the law.
Through faith in Jesus we can bear fruit for God. But if we remain devoted to follow the law and not our faith in Christ, we will continue to follow our sinful desires which the law brings out in us.
Our faith in Christ separates us from the Law and allows us to live in our new nature that comes from the Spirit.
The law is not sin, but it shows us our sin. More rules always means more lawlessness, not more morality. The law gives our sin nature more opportunities to rebel.
The law is perfect but we are not. Therefore, the law shows our imperfection and sin nature very clearly. Because the law is perfect and we are sinful, we cannot follow the law.
The perfection of the law makes our sin very clear, just as any dirt in a glass of clear water would be easy to see. But the water is not the problem, the dirt is. In this same way, sin is the problem, not the law. Our sin nature is shown more clearly because it is carnal, it leads the flesh into sin, whereas the law is perfect and of the spirit.
The sin nature in each person influences what we do and the choices we make. In these verses, Paul is telling us that even if we want to do what we know is good, the sin inside of us can cause us to do those things we don’t want to. Making mistakes is an inevitable part of being a human because we all have a sin nature.
Evil is present in us, even when we are redeemed. Sin’s desire is to hold us captive and obedient to it, acting through the sin nature within us.
It is through faith in Jesus that we are set free from our carnal desires and the sin nature that produces them. While we are still on this earth our sin nature will always be fighting against our desire to serve God.