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:
All Commentaries on Romans 8:3 Go To Romans 8
Augustine of Hippo
AD 430
The reason why grace was bestowed on us through our mediator is that we who were polluted by sinful flesh might be purified by the “likeness of sinful flesh.”