The difference between the living under the Law and living according to the Spirit is huge. There is hardly a comparison. That is why Paul says in today's passage that we serve in a new way. The Amplified Bible puts it this way, "But now we are discharged from the Law and have terminated all intercourse with it, having died to what once restrained and held us captive. So now we serve not under [obedience to] the old code of written regulations, but [under obedience to the promptings] of the Spirit in newness [of life]." ( Romans 7:6 Amp ). It is not out of obedience or obligation but out of a inspiration by the Spirit of God.
We can look at a child to further understand this concept. When you tell a child not to touch the stove because it is hot, they have to obey based on your knowledge. The only knowledge of what is hot comes by your experience. They are choosing to obey according to your understanding of what is hot, not their own. Most of the time, they cannot fathom what hot is, so they will touch it and experience it for themselves. It turns out unpleasant but their understanding then comes from experience and not theory.
The same comparison is true for living under the old nature bound to the Law and living according to the Spirit. When we are bound to the Law, we are bound to the written code. Which is the rules and guidelines and how we should live. However by living this way we are not living out of knowledge and experience but living out of the understanding of another. We are like children without understanding. That is why Paul told us in Galatians 3, "Wherefore the law was our schoolmaster to bring us unto Christ, that we might be justified by faith. But after that faith is come, we are no longer under a schoolmaster. " ( Galatians 3:24-25 KJV ). We only need a schoolmaster as a child. When we are older we have an understanding of our own based on our knowledge not guidelines.
"When faith has come, we are no longer under a schoolmaster." ( Galatians 3:25 ) When we were freed from the Law through faith in Christ we started living by the Spirit. With the Spirit comes an intuitive knowledge base on experience that we did not have under the Law. It is a completely new way of life for us. This knowledge is based on what Christ knows, not based on rules. I Corinthians talks about this. "... God has revealed it to us by his Spirit. The Spirit searches all things, even the deep things of God. For who among men knows the thoughts of a man except the man's spirit within him? In the same way no one knows the thoughts of God except the Spirit of God. We have not received the spirit of the world but the Spirit who is from God, that we may understand what God has freely given us. This is what we speak, not in words taught us by human wisdom but in words taught by the Spirit, expressing spiritual truths in spiritual words. The man without the Spirit does not accept the things that come from the Spirit of God, for they are foolishness to him, and he cannot understand them, because they are spiritually discerned. The spiritual man makes judgments about all things, but he himself is not subject to any man's judgment: "For who has known the mind of the Lord that he may instruct him?" But we have the mind of Christ." ( I Corinthians 2:10-16 ).
Now, by living by the Spirit, we are living out of the newness of life with the Spirit and the mind of Christ as our guide. Our obedience comes from and in-depth understanding of God and not from the mindset like a child trying to live by rules. It is a completely new way of life and in no way compares to the old way. Today I praise God through our Lord Jesus Christ that we are free to live according to the Spirit being guided by Him and living in newness of life.