"God has done what the law...could not do. By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh."
Even as Paul continues in Romans 8 to unfold the marvelous benefits of the gospel, he never forgets what he has already said, and he seeks to make sure that we do not forget it either. In order to appreciate the consequences of the gospel appropriately, we must remember what God has done for us in Christ Jesus alone. The minute we forget that and try to serve God and enjoy the benefits of the gospel without a proper grounding in the gospel, our Christian lives will experience a downward spiral.
Romans 8:1 reminds us that there is no condemnation for those who are in Christ (see 5:1), and today's passage explains why we are not under condemnation. We are never to think that in forgiving us, the Lord simply waves away the just demands of His law and ignores the sentence that His law pronounces upon fallen people. God will never fail to condemn our sin—the only question is where this condemnation will take place. The reason we do not suffer God's condemnation is not because He sets the condemnation aside; rather, it is because the condemnation does not take place in us but in Christ. As the Apostle tells us, our Father "condemned sin in the flesh" of His Son. He did not set aside His law—He upheld it in Christ for our sake (8:2; see Isa. 53; Rom. 3:21-26). Dr. R.C. Sproul writes in his commentary Romans that "in [God's] Son, there is no condemnation for His people. There is condemnation for their sin, but it is condemned in Christ and removed."
It was because our Savior came in the likeness of sinful flesh that this could be accomplished. Here Paul is using the term flesh as a synonym for human nature as it was originally created and not as an identifier of those aspects of people that are opposed to God. To be the true mediator between God and human beings, the Son of God had to take on a human nature and live as a human being. His human nature is entirely in common with ours except for one thing—it never suffered the effects of the fall. Christ is a true man, but He is said to have the likeness of sinful flesh because His flesh—His humanity—has never been tainted by sin. The early church father John Chrysostom writes, "Christ did not have sinful flesh but flesh which, though it was like ours by nature, was sinless. From this it is plain that flesh is not sinful by nature. It was not by taking on a different kind of flesh nor by changing ours into something different that Christ caused it to gain the victory over sin and death."
Coram Deo
Paul is insistent that Jesus is the answer to sin because He has done what God's law cannot. It is not the law's fault that it cannot justify sinful people; rather, it is our fault. Outside of Christ, our fallenness takes hold of the law, and we are unable to fulfill it. The good news of the gospel is that God sent His Son to do what we could not do even with the help of the law. Such is the nature of His grace—grace for which our gratitude must never cease.