Romans 8:3-4
(3) For what the law could not do, in that it was weak through the flesh, God sending his own Son in the likeness of sinful flesh, and for sin, condemned sin in the flesh:
(4) That the righteousness of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit.
Having stated the fact of freedom, Paul then explained how it is achieved. He declared again the impossibility of attaining freedom over sin through the (Mosaic) Law. It was powerless to free from sin. Not that the Law was weak in itself (as many translations suggest), for it was good (7:12). But because of sinful human nature, the Law could not deliver from sin. The words “sinful nature” translate sarx (lit., “flesh”), which can mean either human sinful corruption or human weakness (cf. 7:5, 18, 25; 8:4-5, 8-9, 12-13).
God accomplished deliverance over sin, however, by sending His own Son in the likeness of sinful man (lit., “likeness of flesh of sin”). Jesus was sent not in sinful flesh but in the likeness of it. His human nature was protected and preserved from the indwelling principle of sin that has plagued all other human beings since Adam (cf. Luke 1:35). He was also sent, literally “concerning or for sin” (peri harmartias, not as the niv has it, to be a sin offering). In other words He came to do something about sin. What He did was to condemn it; by His death on the cross, He condemned sin (katekrinen, “passed a judicial sentence on it”; cf. katakrima, “punishment,” Rom. 8:1) so that those in Christ are not condemned. The goal of this was so that the righteous requirements of the Law—a life of holiness (Lev. 11:44-45; 19:2; 20:7)—could be fully met as believers do not live according to the sinful nature but according to the Spirit. The provision of deliverance from the power of sin is through the death of Jesus Christ, but experiencing it in one’s daily conduct comes through the controlling power of the Holy Spirit.
Excerpt from:
Walvoord, J. F., Zuck, R. B., & Dallas Theological Seminary. (1983-c1985). The Bible knowledge commentary : An Exposition of the Scriptures. Wheaton, IL: Victor Books.
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