How are those who walk according to the Spirit different from those who walk according to the flesh?

Romans 8:4–6, Romans 8:12–13

This proper functioning of the good law manifests in the lives of people who are no longer governed by their own flesh, that is, their own sinful nature, but by the Spirit of God who comes to live in them. The phrase at the end of Romans 8:4 is already found in Romans 8:1 in most manuscripts. Here Paul is writing about people who walk not according to the flesh but according to the Spirit. The verb walk here refers to man’s walk of life. Since Paul now places flesh and Spirit parallel with each other, it may here appear as though man here merely receives a different perspective. This would not have solved anything, however, for even in the life according to the Spirit human weakness could still make a return. Paul, however, actually here contrasts two very different matters. The flesh indicates human nature inasmuch as it is not governed by law or reason. This flesh therefore needs to be controlled, subdued, and regulated. The Spirit is a living Person who leads us. He rules personally. Life according to the flesh is in actual fact a life falling apart, whereas a life according to the Spirit is a life that is being governed and led by that Spirit.

In Romans 8:5 Paul writes: For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit set their minds on the things of the Spirit. With this he indicates the transition from a self-governed life to a life that is being governed. The Spirit is, after all, more than a mere precept. He is the Living One himself. In this sentence we find another parallel contrasting two different matters. That which our own nature desires is an inner process through which we can remain true to ourselves. The will of the Spirit for us, however, is a process in which we allow ourselves to be led by Another.

The difference becomes even clearer when we look at the effect of these two different lifestyles: For to set the mind on the flesh is death, but to set the mind on the Spirit is life and peace (Romans 8:6). Living lives ruled by our own nature leads to all sorts of loveless actions and ultimately to death (for a more detailed discussion on this, see Romans 1:18–32). The Spirit has a radically different program for us, however, namely to give us life and to establish peace with God. In Romans 8:6 the net effect of setting your mind on the things of the flesh versus setting your mind on the things of the Spirit is highlighted. By following your passions and falling short in your love towards God’s law, you become a victim of the destructive operation of the flesh and its misdirected passions. On the other hand, those who follow the guidance of the Spirit of God come to share all that this Spirit is, brings, and wants. He is the Spirit who gives life and creates harmony.

The Greek word sarx, translated as flesh, refers to the desires and impulses that live within people and over which they must rule and which they must direct either with their mind (in the case of the Greeks) or with the law (in the case of the Jews). The fact that we so often fail to do this and that unkindness and aggression prevails in all human relationships (Romans 1:18–32) is because, as Paul has pointed out (Romans 5:12–21), sin has come into this world. Sin incentivizes people to give their desires and selfish impulses free rein (Romans 7:7–24). As such, people, whether they desire to or not, become slaves of their natural impulses. Yet now the Spirit intervenes, and when that Spirit comes to live in us, we are thankfully no longer obliged to serve ourselves, for living for yourself, that is walking according to the flesh leads to death (See also Romans 1:32, Romans 5:12–21, Romans 7:7–10). What then is the alternative? Naturally it is a life lived for the Spirit.¹