Ambrose of Milan

The apostle says, "For God, sending his own Son in the likeness of sinful flesh, and for sin condemned sin in the flesh, that the righteousness of the law might be fulfilled in us." He does not say "in the likeness of flesh," for Christ took on himself the reality, not the likeness, of flesh. Nor does he say in the likeness of sin, for he did not sin but was made sin for us. Yet he came "in the likeness of sinful flesh." That is, he took on him the likeness of sinful flesh, the likeness, because it is written, "He is man, and who shall know him?" He was man in the flesh, according to his human nature that he might be recognized, but in power he was above humanity, that he might not be recognized, so he has our flesh but has not the failings of this flesh.