Both Scriptures and the writings of the fathers support the knowledge that all men are tempted by the seduction of sin. Being ordained into the priesthood or bishopric does not guarantee that one will never fall away from the faith or never sin. If only the righteous are able to represent God then God would have no representatives worthy on earth.
Contrary opinions are similar to the teachings of the heresy of Donatism that stated that the sacraments administered by a priest in mortal sin are invalid and conveyed no grace to the recipient. Obviously, this is false teaching as no one could ever be assured of the grace as no one can be sure of the moral state of another. The fact is that the errors or sinfulness of a priest has no effect on the sacraments received as the priest is acting “in persona Christi” which means that Christ is acting through the priest, the priest being His hands and His mouth. In the case of an absolution the principal of “Ecclesia supplet” which grants one absolution regardless of whether the priest had valid authority to give absolution.
The sins of the flesh are seductive even to the most righteous among us. It is through God’s grace that we retain our “free will” and may sin and fall away from the faith. God did not base the authority or righteousness of the Church on the ability of men to remain free of sin but on His own divine righteousness shown to us on earth. This is a goal of which we have hope but no assurance except on Him who died for the atonement for us. It is His Holiness and His truth and not that of men that makes His Church the “bulwark and ground of the truth”.