Were there any saints who criticized the church?

> Pope Francis has said that those who constantly criticize the Catholic > church are “friends of the devil”. My question is: were there any saints in history who repeatedly criticized the church or the church leaders? I know there was St. Catherine who was urging popes move to Rome > spent twenty years trying to convince popes to move back to the > Eternal City But I wouldn't consider this as a criticism, it's more of a strategical guidance. I'm more interested in public moral criticism. Note: I mean the saints who were already living their life of sainthood. After their conversion and through their mystical life were instructed or led by the Holy Spirit to criticize certain immorality of the Church's leaders.