It is the Spirit of God who is our internal moral compass. He directly influences us away from the lusts of the flesh by expressing to us His desires for what we should think and do (
Gal 5:17). Walking as He infuences us to walk is the only way to avoid fulfilling the lusts of the flesh (
Gal 5:16).
When we received God's Spirit by faith, His entry into our hearts created a new being (a spiriual being) that did not exist before. That new creature is truly righteous and holy (
Eph 4:24) because it is joined to the Lord and is one spirit with Him (
1 Cor 6:17). It is because of His presence and our oneness with Him that we love God with all our hearts and love our neighbors as ourselves. His presence and our oneness with Him is the reason that all the law's requirements for righteousness are fulfilled (
Rom 8:4).
Now that we have become new creatures in Christ with new hearts, and now that we have Him as our internal leader and guide, we do not look to the law the same way we did when we were lost. When we were lost, the law condemed us to hell. It taught us that everyone is a sinner (
Rom 3:23) and that the wages of sin is death (
Rom 6:23). It convinced us that every sin counts against us (
Gal 3:10) and that breaking one commandment makes us guilty of all (
Jas 2:10). The law could only condemn us because it had no way to bring life (
Gal 3:21) and it had no way to bring about righteousness (
Ga 2:21).
Thankfully, God did the thing for us that the law could not do. He sent His Son to die for our sins, and through our faith in Him we gained life (His life) and righteousness (His righteousness) through union with Him...
3 For what the law could not do in that it was weak through the flesh, God did by sending His own Son in the likeness of sinful flesh, on account of sin: He condemned sin in the flesh, 4 that the righteous requirement of the law might be fulfilled in us who do not walk according to the flesh but according to the Spirit. (
Ro 8:3–4)