There are two ways of living for a human. One is to live according to the spirit, and the other is to live according to the flesh. A human is made of a spirit, a soul, and a body. The body is simply a physical entity controlled by a personal being. But both the spirit and the soul are beings, and each has its own personality with will, reason and emotions. A car has only one driver’s seat with one steering wheel, and the person who sits at the driver’s seat can move the car wherever he/she desires to go. In the same way, the spirit or the soul, whichever sits at the throne of your heart controls your entire being as it wills and desires.
Needless to say, the “spirit” as discussed above is a human spirit, not the Spirit of God. In discussing the “spirit,” we first need to clarify what kind of spirit we are dealing with. Keep in mind that the word “Spirit” with a capital “S” in our English translations is a result of the particular interpretation given by our translator(s). In Greek, it is simply “pneuma,” and it could mean God’s Spirit, or a human spirit, or any kind of a spirit. Since our churches in the past knew so little about the spiritual beings and their world, there has been a great deal of confusion in the interpretations of this word and the other related terminology. However, the other side of the coin is that as you study the scriptures more in depth, you will be amazed with the fact that the writers of the New Testament knew so much about the spiritual beings and their world including the spiritual aspect of a human being. That is why the Bible is the Bible.
The Spirit himself testifies with our spirit that we are God's children (Rom 8:16).
Note that “the Spirit” is distinguished from “our spirit” in this verse. Here, you can see easily from the context of vv. 9ff that “the Spirit” with a capital “S” meaning the Spirit of God is correct in its interpretation. And this “Spirit” is differentiated from “our spirit” by the pronoun “our.” What this verse teaches is that it is God’s Spirit, or God himself, not us, who testifies that we believers are God’s children being heirs of God, and coheirs with Christ. God himself testifies and confirms it for us against Satan and his world. And the important thing is that he does it “with our spirit”—not with our body, or soul (or flesh).
Yet, you remember the following verse:
For if, by the trespass of the one man, death reigned through that one man, how much more will those who receive God's abundant provision of grace and of the gift of righteousness reign in life through the one man, Jesus Christ (Rom 5:17).
It is “those who receive God’s abundant provision of grace and of the gift of righteousness” who reign in life. And we have the following scriptures as well:
Submit yourselves, then, to God. Resist the devil, and he will flee from you (James 4:7).
Resist him, standing firm in the faith (1 Pet 5:9).
We “resist the devil.” We cannot expect God or Christ to do it for us. Amen! But aren’t you one of those who tried to reign over your circumstances without success? You wonder why it did not work for you. Well, biblical principles often do not work when our knowledge of the Bible is partial and limited to certain parts of the whole truth. The Bible is one truth in its entirety. We need to look at other parts of the Bible to see what is missing. The key lies in Rom 8:16, which appears to be contradicting with the principle we have already learned.