Paul is writing to people who want to be righteous. He is not speaking to all mankind, some of whom desire nothing better than to do evil all day. He is writing to people searching for the means to be righteous. It is because they wished to be righteous that the Galatians were drawn away from Christ by the party of the circumcision that brought them under the Law. With this as a background, Paul submits his argument concerning two powers—the flesh and the Spirit.
Paul argues that the two powers within us are the flesh and the Spirit, and they are opposing powers. So, in the context of wanting to be righteous, Paul argues that the flesh will not allow me to be righteous, which is what I want (Galatians 5:17). It even takes advantage of the Law by influencing one to do those things he is commanded not to do (Romans 7:15-19). The Law is a guide. It can point toward something or away from something else, but it is powerless to aid one to do what it commands. On the other hand, the flesh is a very powerful influence to do evil.
Nevertheless, Paul argues, if I walk after the Spirit, I will not fulfill the desires of the flesh (Galatians 5:16). What does this mean? I remember when I was a young man. I had very little success concerning a particular sin. It was my master. No matter how hard I tried to avoid sinning, when an opportunity presented itself, I had no strength to avoid the inevitable. On one occasion, however, instead of even thinking of fighting the sinful opportunity that presented itself, I began to praise Jesus for what he has done for me. I was astonished that for the very first time in my life the temptation had lost its power over me. I wasn’t trying not to sin; I was simply praising God. I discovered, for the first time, the power of the Spirit. Suddenly, this Scripture became clear to me. I could be controlled by either the Spirit or the flesh, but not both at the same time. I discovered that I am able to lay aside the sin that so easily overpowers me, if I fix my eyes (my thoughts) on Jesus (Hebrews 12:1-2).
For the first time in my life, I understood how the Law—even the Ten Commandments—are not needed to help me to be righteous. All I need is Jesus. If I am led by the Spirit, I will not sin. Jesus did not sin. Therefore, the Spirit of Jesus will not lead me into sin. I can trust Jesus to make me righteous. This is Paul’s argument here in Galatians. He offers a list of the fruits of the flesh, which are not only sinful in themselves, but some of these activities are even held in check by the laws of men. However, when Paul comes to the fruit of the Spirit, he points to love and there is no law of man or God that is against love or any of its expressions, which Paul also lists. To love, therefore, fulfills the command of the Law (Galatians 5:14), but love is not the fruit of law, but of the Spirit. Therefore, it is the Spirit, not Law that is able to make me righteous.
We who are Christ’s have crucified the flesh (Galatians 5:24), that is, we have rendered it powerless by receiving Christ by faith. So, if, indeed, we have the new life dwelling within us, we need to follow through and live by that Spirit-life (Galatians 5:25) and not the life of the flesh. An American Indian Christian was asked by a preacher what he thought the Christian life was like. He said it is like having two dogs within who were constantly fighting. The preacher asked: “Who is winning?” The man responded: “Whichever one I feed the most!” Such is Paul’s argument. Walk in the Spirit and we will not fulfill the desires of the flesh!