In Romans 8:9-11, the Apostle Paul contrasts living by the Spirit with living by the flesh. And the choice is a matter of life and death. Christians today confuse the experience of the Holy Spirit with something emotional or as some sort of loss of one’s control. However, all Christians—by virtue of being in Christ—have the gift of the Holy Spirit touching their lives. They can potentially live according to the Holy Spirit.
We need to begin by understanding the difference between the flesh and the Spirit since Paul begins this passage saying, “You are not in the flesh; you are in the Spirit, since the Spirit of God dwells in you” (NRSV). The flesh—as far as Paul is concerned—is not strictly the carnal desires for excessive drinking, drugs, or explicit sex. It would include that to be sure but the flesh is also the impulse to make gods out of material things (idolatry), retaliation and division, envy and gossip (see Galatians 5:19-21). Flesh is that has the death embedded within it. The Spirit is the Spirit of God or of Christ that sustains and gives life.
Prior to his conversion, Paul (Saul) would have said that the way to accomplish what God desires of a person, they must follow the commandments. The post-conversion Paul came to understand that such a discipleship by sheer force of will could not be accomplished. Rather, the Holy Spirit comes to people’s lives and the lives of communities of faith as a gift. The Spirit of God is the Spirit of Jesus Christ. And those who follow Jesus seek to follow the Spirits guidance. Those who have the Spirit set their mind on the Spirit (8:6-7). They experience life and they experience peace. Paul envisioned the unfolding of life in the Spirit as a progressive movement as the Holy Spirit influences more and more of our lives.
It can include a strong emotional experience, but it also includes deep conviction, intellectual illumination, and moral impact. In short, all that makes life real life—human living in its truest sense—comes as the result of people responding to and taking the mind of the Holy Spirit.