For God has done what the law, weakened by the flesh, could not do. By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh, in order that the righteous requirement of the law might be fulfilled in us, who walk not according to the flesh but according to the Spirit.
Seven expressions in these two verses warrant comment:
1. For God has done.
Religion is spelled D-O, what we do, what we achieve. The gospel is spelled D-O-N-E, what God has done, what we receive. Salvation is not the work of man for God, but the work of God for man.
2. The law, weakened by the flesh.
The problem is not the law, but our flesh - our sinful, selfish tendency that we are born with. Because of our sinfulness, the Old Testament law could not justify us (make us right with God) and could not sanctify us (make us holy).
3. By sending his own Son.
The incarnation and crucifixion reveal the sacrifice of the Father. This is his own Son, the Son of his love, that he has sent to save us.
4. In the likeness of sinful flesh.
His humanity was real but he was without sin. So in the incarnation, Jesus came in the likeness of sinful flesh.
5. For sin.
This is why God sent his Son - for sin, to pay for sin, to atone for sin, to obliterate our sin. Jesus came for sin.
6. He condemned sin.
Jesus paid for sin. He defeated sin. He condemned sin. The only reason sin does not condemn us is because Jesus has already condemned our sin.
7. Who walk not according to the flesh but according to the Spirit.
We become more and more holy, more and more Christlike, not by the flesh, our own efforts, but by the Spirit, the Spirit who infuses us with power. We depend upon the Spirit, and therefore we are empowered by the Spirit.
Lord, help me to live my life depending on you, on your Spirit, and not upon me, my trying hard.