The Sacrament of Penance (also commonly called the Sacrament of Reconciliation or Confession) is one of the seven sacraments of the Catholic Church (known in Eastern Christianity as sacred mysteries), in which the faithful are absolved from sins committed after baptism and reconciled with the Christian community. During reconciliation mortal sins must be confessed and venial sins may be confessed for devotional reasons. According to the dogma and unchanging practice of the church, only those ordained as priests may grant absolution.
The church teaches, based on the Parable of the Prodigal Son, that confession is not a tribunal or criminal court, where one is condemned by God like a criminal, but a "wedding banquet hall, where the community celebrates Easter, Christ's victory over sin and death, in the joyful experience of his forgiving mercy." In confession, the church believes, God judges a person in the sense of bringing to light his or her sins, by granting the person the ability to confess his or her sins to the confessor, then grants the person repentance and, through the confessor, grants the person forgiveness. God's forgiveness restores the person to "the brightness of the white robe of baptism, a garment specifically required to participate in the [wedding] feast."
In the New Testament, Christians are admonished to "confess your sins to one another and pray for one another" at their gatherings, and to be forgiving people. In the Gospel of John, Jesus says to the Apostles, after being raised from the dead, "Receive the Holy Spirit. Whose sins you forgive, they are forgiven; and whose sins you shall retain, they are retained". The early Church Fathers understood that the power of forgiving and retaining sins was communicated to the Apostles and to their lawful successors, the bishops and priests, for the reconciling of the faithful who have fallen after baptism.
In the middle of the 2nd century, the idea of one reconciliation/penance after baptism for the serious sins of apostasy, murder, and adultery is suggested in the book of visions, The Shepherd of Hermas.