"The Church is sinless, but not without sinners," said Cardinal Journet. Not without sinners, we know it only too well. She is sinless in the sense that in spite of the indignity of her ministers, she offers all the help and graces of sanctification needed for my eternal salvation: the Mass, the sacraments, the veneration of the Blessed Mother and the saints, the Magisterium, etc.
This is why I trust her. Indeed, even if a priest guilty of serious sin celebrates Mass and consecrates the bread and the wine, the consecration is valid. The Lord is really present, because the supernatural "power" to consecrate comes from the sacrament of Holy Orders and this "power" is independent of the priest’s morality.
The Lord has so arranged that the people of God will never be deprived of divine food. Similarly, if I confess my sins to an unworthy priest, the sacramental absolution that he gives me is also valid. Of course, I will only be forgiven if my repentance is sincere.
Father Jean Richoz, pastor of Cugy (Canton of Vaud, Switzerland)