The Christian life seems to be very mysterious and abstract, but Paul made it practical by speaking about the flesh on the negative side and the spirit on the positive side. This is the human spirit, not the Holy Spirit. The human flesh and the human spirit are the keys to the practical Christian life. If we are going to experience life in a practical way, we must be clear about the flesh and the spirit.
Not many Christians today are clear about these two things. We may have read Romans 6—8 and may be familiar with the flesh and the spirit as terms, but what we need is a heavenly vision, a divine revelation. Many Christians have read through Romans 8 and have seen the Holy Spirit, but they have not seen that there is another spirit in this chapter. Verse 16 says, "The Spirit Himself witnesses with our spirit." This verse speaks of the Holy Spirit and our spirit, the human spirit.
Christians mostly pay their attention to the first Spirit, the Holy Spirit. But we cannot realize the Holy Spirit without our human spirit. Regardless of how wonderful the Holy Spirit is, we must have the proper organ, our human spirit, to realize Him. If we do not have eyes, we cannot realize what light, colors, and beautiful scenery are. Our eyes are the proper organ to realize these things. If we did not have our ears as a listening organ, we would not be able to realize or substantiate any sounds. God is Spirit. If we did not have our spirit, we could not substantiate Him.
In the previous chapter, we saw that Satan, sin, and death are all in the flesh. We must be able to present the verses from the Scripture which prove this. Romans 7:17 says, "It is no longer I that work it out, but sin that dwells in me," and verse 18 says, "I know that in me, that is, in my flesh, nothing good dwells." These two verses show that sin dwells in the flesh.
Now we need to consider how we can say that sin is Satan. Verse 21 says, "I find then the law with me who wills to do the good, that is, the evil is present with me." When sin is dormant within us, it is merely sin, but when it is aroused in us by our willing to do the good, it becomes "the evil." That means sin is the evil and the evil is sin. In the New Testament Satan has another title, and this title is "the evil." In John 17 the Lord prayed that the disciples would be kept from "the evil one," but in the Greek text the word one is not there (v. 15). Who is "the evil"? The evil is Satan and evil is sin, so sin is Satan.
Sin in Romans is a living person, because sin can kill us, deceive us (7:11), and lord it over us (6:12, 14). It is no longer I who do it, but sin that dwells in me. I am a person, and sin is also a person. In Galatians 2:20 Paul said, "It is no longer I...but...Christ who lives in me." Within me, the person, there is another Person—Christ. Also within me, that is, in my flesh, there is another person. This person is sin, and sin is Satan. Sin is Satan dwelling in us, and death is one with sin. Romans 8:2 speaks of the law of sin and death. So as long as you have sin, you have death. These three things—Satan, sin, and death—are all in the flesh.