The apostle Paul also tells us that the Law given through Moses to Israel was “weak through the flesh,” the imperfect flesh of those who were under the Law. The Law under which the Aaronic priesthood served was spiritual, from God, but by it fleshly persons “sold under sin” were condemned, instead of being pronounced righteous. (Ro 8:3; 7:14; Heb 7:28) The high priests of the fleshly line of Aaron assigned by the Law were not able to offer an adequate sacrifice for sin.​—Heb 7:11-14, 23; 10:1-4.

Jehovah proved that human flesh can be sinless. “God, by sending his own Son in the likeness of sinful flesh and concerning sin, condemned sin in the flesh.” (Ro 8:3)