The Mortification of Sin, by Dr. Philip G. Ryken

This past Sunday (2/28) Dr. Ryken preached a sermon on the mortification of sin from Romans 8:12-13.  It seemed pertinent to our discussion on this blog, so we have posted an excerpt below.  You can access the text of the entire sermon here or the audio and video here.


The doctrine of the mortification of sin enters Romans 8 as the conclusion to everything the apostle Paul has been saying about the flesh and the Spirit—“the two great powers of salvation history.” The flesh is everything “that is characteristic of this life in its rebellion against God.” The Spirit, of course, is God himself, in the person of his Holy Spirit—the third member of the Trinity. Paul has told us that this flesh and this Spirit are in absolute opposition to one another. He has told us that having a fleshly mindset is fatal. He has told us that people who are in the flesh do not and cannot please God. But he has also told us that when we have God’s indwelling, life-giving Spirit, we have Christ himself, and we will live.

Verse 12 marks a transition. The words “so then” indicate that the apostle is drawing a practical conclusion. He is taking the life we have in the Spirit and showing us how to live it. He is doing this in a very personal way. Notice the word “brothers.” Our dear brother Paul is coming alongside us in love to teach us what he has learned about daily discipleship: “So then, brothers, we are debtors, not to the flesh, to live according to the flesh. For if you live according to the flesh you will die, but if by the Spirit you put to death the deeds of the body, you will live” (Romans 8:12-13).

Back in verse 4 Paul talked about how “the righteous requirement of the law of God might be fulfilled in us, who walk not according to the flesh but according to the Spirit.” Now he continues the contrast between the Spirit and the flesh by saying that we have an obligation to the one but not to the other. The word “debtors” gives a strong sense of duty. There is something that we are absolutely obligated to do, but whatever that obligation is, it is not to lead a fleshly way of life. On the contrary, we are called to righteous living.

There is something here that we need to remember every time we are tempted to sin: we are under absolutely no obligation to commit whatever sin it is that is tempting us. Sometimes the temptation is so strong that we feel powerless to resist it. So we give in to having a bad attitude, or go ahead and make an angry comeback, or indulge in sexual sin, or walk right by someone in need, or inwardly congratulate ourselves for not committing the sins that other people commit.

When we feel powerless against these and other temptations, it is good to remember that we owe our flesh absolutely nothing. If we were in the flesh, then we would be obliged to commit all kinds of sins. In fact, we wouldn’t be able to help it. But that is not the way we have to live. The Spirit of life has set us free in Christ “from the law of sin and death” (Rom. 8:2). Therefore, we do not have any kind of duty to sin.

In fact, we had better not sin, because in verse 13 Paul goes on to say that people who live according to the flesh will certainly die. He is not talking here about mere physical death. He talked about that back in verse 10, where he said that “the body is dead because of sin.” There he was talking about physical death, and what he said applied not just to unbelievers, but also to Christians. Whether we are living in the flesh or living by the Spirit, we are all destined to die—even people who are in the Spirit and will rise again.

But here in verse 13 Paul is talking about people who “live according to the flesh,” specifically about their spiritual death. “What is meant,” writes Leon Morris, “is death in its fullest theological sense: eternal separation from God as the penalty for sin.” By this definition, some people are dead already. There is no spiritual life in them. Although they have not yet fallen under God’s everlasting judgment, they are as good as dead, because they do not have the life-giving Spirit of God.

This is a sober warning for anyone who is not leading a holy life, but deliberately sinning against God. Do you still expect God to save you in the end? James Boice gave the following warning, based on these verses: “Paul is saying that if you live like a non-Christian, dominated by your sinful nature rather than living according to the Holy Spirit, you will perish like a non-Christian—because you are a non-Christian.”