One of the sacraments teached by the Catholic Church is the sacrament of Confession wherein a member will tell everything that he has done to a priest. Later on the priest will tell the person to pray some repetitious prayer before the altar for his sins to be forgiven. However, why would you tell your sins to the priest? If you are suppose to confess your sins, the bible says that we should confess it to God and to the person whom we have offended.
I acknowledge my sin unto thee, and mine iniquity have I not hid. I said, I will confess my transgressions unto the LORD; and thou forgavest the iniquity of my sin. Selah.
Confess your faults one to another, and pray one for another, that ye may be healed. The effectual fervent prayer of a righteous man availeth much.
According to history, confession has been use by the Catholic Church in order to suppress heresy. Rebels against the Church and the State were exposed because their members of their family would often go the Priest and confess of what they know.