Romans 7:18 For I know that in me (that is, in my flesh,) dwells no good thing: for the will to do is present with me; but how to perform that which is good I find not [within my flesh].
Just as with all knowledge, how to perform that which is good must be modeled to succeeding generations (pun intended). Paul discusses in Romans Chapter 7 the union of carnal commandments and the sinful nature of man. He discovered that the fallen nature tends to lead us to violate the precepts we hold dear and holy. When we learn that there are right ways and wrong ways, THEN the fallen nature of the carnal heart leads us all into sin (or worse).
Paul had previously stated that the wrath of God is revealed from heaven against all the ungodliness of men, who suppress the truth in unrighteousness. Why? Because what may be known about God is manifest in them, BECAUSE God has shown it to their hearts (Rom 1:18-19). Therefore the struggle to do right rages within all, regardless of the culture, and all are without excuse as to whether or not they sin.
After we discover that we have violated the rules of our conscience, THEN Holy Spirit initiates the conviction process. One's reaction to HIM determines whether a person discovers his need for a savior or whether he exchanges the truth about his depravity for a lie .
Furthermore, like a husband has sway over a wife, we are under the dictates of this sinful nature whether we agree wholeheartedly with it or not. Too often, I tend to excuse my shortcomings as mistakes instead of seeing the fact that I have complied with a nature that was supposed to crucified. In Romans Chapter 7, Paul says that Law is the husband who dies. Death to this law came through the sacrifice of Jesus; who paid itse penalty and bought our freedom. Now I may marry another (the Laws of the Kingdom) and, as a bride, fulfill that husband's desires [Other analogies about marriage notwithstanding].
Therefore, I am not my own; I have been bought with a price (1Cor 6:19-20). I am free to serve the Lord because HE has given me the ability to overcome the dictates of my flesh and of my old nature. What is still in me IS NOT greater than WHO is now in me! I can do all things (God commands) through Christ who strengthens me (Phil 4:13).
Therefore we are no longer debtor-slaves to carnal natures mindlessly obeying the lusts thereof (Rom 6:11-12), but we are free from our old nature and have become the espoused of the Son of God. Let His mind be in us, so that we ignore the fallen will that is in our flesh. AMEN