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June 18, 2024

The Law of Sin and the Grace of Christ

Free Daily Devotionals from Open the Bible

What follows is an excerpt of The Enemy Within: Straight Talk about the Power and Defeat of Sin by Kris Lundgaard. Get your copy of the book this month for a gift of any amount.


If we want to stand in conquest over our [battle against the] flesh, we’ll have to follow Paul into the fight. When we do, we’ll find the same four truths that humbled him in battle, all expressed in one verse:

So I find this law at work: When I want to do good, evil is right there with me. (Romans 7:21)

1. Sin living in us is a “law.”

The “law” Paul refers to is the same thing he calls “sin living in me” in verses 20 and 23. This is the indwelling sin we are talking about. Why call it a law?

Paul uses “law” as a metaphor. He needs a way to express the power, authority, constraint, and control that sin wields in our lives, and he picks “law” with a touch of irony. He has been writing earlier in the chapter of God’s law, which is supposed to rule our lives, yet the law of sin seems to win a lot of head-to-head battles. Could he have chosen a more stunning contrast to unmask sin’s deadly force?

Chew on the metaphor of law for a minute. We can think of it in one way as a moral rule that directs and commands us to do what it requires (“Honor your parents”) or not do what it forbids (“Do not trespass”). More than that, a law entices us to obey with offers of reward (“you will live long in the land”) and compels us to submit by threats of punishment for disobedience (“$500 fine for trespassing”).

We can also think of law in the way we speak of “laws of nature.” Gravity, for example, is a law that bends things in its direction. It perfectly conforms us to its “commands.” Gravity is not a law as an idea or an outward precept, but a force that can make objects “obey” its “will.” In this sense every urge and inclination in us is a law. Hunger is a law, thirst, sexual drive, fear—each impels us to fulfill its demands, and each brings a force to bear on us to bow us into submission.

Indwelling sin works like this—enticing, threatening, even bullying. So Paul calls it a law to get us to see that it is powerful even in the lives of believers and that it constantly works to press us into its evil mold. That raises the question, “In what sense has Christ defeated sin in the believer?” The answer is that he has overthrown its rule, weakened its power, and even killed its root so that it cannot bear the fruit of eternal death in a believer. Still—and this is amazing but true—sin is sin; its nature and purpose remain unchanged; its force and success still grab us by the throat.

2. We find this law inside us.

Paul had heard horror stories about sin all his life. He had seen countless bony fingers waving in his face to warn him of sin’s power. But in Romans 7:21 he moved from cozy theory into troubling experience: he found this law. It is one thing to sit in a group and critique dissertations on original sin; it is something else to find yourself subdued by its strength and madness. It is one thing to listen to a lecture about AIDS—how it spreads, what it does to a body, how invincible it is; it is another thing to hear your doctor say to you, “HIV-positive—I’m sorry.”

Few people have come to terms with the law of sin. If more people had, we would hear more complaints of it in prayers, see more struggling against it, and find less of its fruit in the world. When we find this law in us, Paul’s “Who shall deliver me?” echoes down our bones.

Believers are the only people who ever find the law of sin at work in them. Unbelievers can’t feel it. The law of sin is a raging river, carrying them along; they cannot measure the force of the current, because they have surrendered themselves to it and are borne along by it. A believer, on the other hand, swims upstream—he meets sin head-on and strains under its strength.

3. We find this law when we’re at our best.

As powerful as this law of sin is, it doesn’t rule the heart of the believer. Paul found it at work in him even while he wanted to do good. He didn’t stumble onto it in a time of great backsliding, or when he was indifferent about the things of God. He was aware of it even when he most wanted to serve God, when he set his mind to obey his Savior and King, when Christ ruled his heart.

Though the law of sin works from the inside and ambushes believers at their best, it isn’t their dictator. Believers march to a different Drummer: “I want to do good,” Paul says (Romans 7:21)—I want to please God, give him glory, serve his people, honor his name. By God’s grace the desire to obey him ordinarily prevails in us, even against this insidious enemy within.

4. This law never rests.

Since grace rules the believer’s heart, he wants to do good. We can describe that desire in two ways. First, there is his general and constant desire to please God (verse 18). Second, there are times when the believer has a particular duty in mind that he wants to perform, such as private prayer or giving a tenth of his income to God (“When I want to do good”— verse 21). The law of sin opposes both.

The “law of sin and death” is in a constant tug of war against the believer’s overall desire to please God (verses 14–25). But sin goes further: when the believer sets his jaw to even the simplest duty to God, sin fights him right at that point (“Evil is right there with me”— verse 21), making him drowsy or distracted when he would pray, or stingy and ambitious when he would tithe.

Don’t you sometimes feel like Dr. Jekyll and Mr. Hyde? Every believer who is also a sinner (which is every believer) does. “For the sinful nature desires what is contrary to the Spirit, and the Spirit what is contrary to the sinful nature. They are in conflict with each other, so that you do not do what you want” (Galatians 5:17).

Who shall deliver me?

Wise Up

We are at the beginning of obedience to God. To understand these four truths about indwelling sin is to arm yourself against it. In your struggle against sin, there is only one thing more important to grasp than these four facts: the free, justifying grace of God in Christ’s blood. The grace of God in Christ and the law of sin are the two fountains of all your holiness and sin, joy and trouble, refreshment and sorrow. If you are to walk with God and glorify him in this world, you need to master both.

Suppose there is a kingdom that has within its wall two mighty opposing forces. The subjects of the king are at odds, always plotting and feuding against each other. If the king is not wise, his kingdom will be laid in ruins. The law of sin and the law of the Spirit of life (Romans 8:2) in us are mortal enemies. If we are not spiritually wise in managing our souls, how can we help making a wreck of ourselves?

But many people live in darkness and ignorance about their own hearts. They keep careful track of how their investments are doing on Wall Street and get frequent checkups at the doctor; they watch what they eat and work out at the gym three or four times a week to keep their bodies finely tuned. But how many people give the least thought to their souls? If it is important to watch over and care for our bodies and investments, which will soon die and rot, how much more important is it for us to guard our immortal souls?

Getting to know indwelling sin, as humiliating and discouraging as it can be, is our wisdom—if we have any interest at all in finding out what pleases the Lord (Ephesians 5:10) and avoiding everything that grieves his Holy Spirit (Ephesians 4:30).


Taken from The Enemy Within by Kris Lundgaard ISBN 9781629959559. Used with permission from P&R Publishing P O Box 817, Phillipsburg N J 08865  www.prpbooks.com.