What is the relationship between penance and the other sacraments? The Rite of Penance suggests a close link with the grace of forgiveness received in baptism:
2. This victory is first brought to light in baptism where our fallen nature is crucified with Christ so that the body of sin may be destroyed and we may no longer be slaves to sin, but rise with Christ and live for God. [See Rom 6:4-10.] For this reason the Church proclaims its faith in “one baptism for the forgiveness of sins.”
The Eucharist also reminds us of the salvific ministry of Christ:
In the sacrifice of the Mass the passion of Christ is again made present; his body given for us and his blood shed for the forgiveness of sins are offered to God again by the Church for the salvation of the world. For in the Eucharist Christ is present and is offered as “the sacrifice which has made our peace” [See RM, Eucharistic Prayer III.] with God and in order that “we may be brought together in unity” [See RM, Eucharistic Prayer II.] by his Holy Spirit.
Through the service of those in Holy Orders, the members of the Church experience the grace of reconciliation:
Furthermore, our Savior Jesus Christ, when he gave to his apostles and their successors power to forgive sins, instituted in his Church the sacrament of penance, Its purpose is that the faithful who fall into sin after baptism may be reconciled with God through the restoration of grace. [See Council of Trent, sess. 14, De sacramento Paenitentiae cap. 1: Denz-Schon 1668 and 1670; can. 1: Denz-Schon 1701.] The Church “possesses both water and tears: the water of baptism, the tears of penance.” [Ambrose, Ep. 41, 12: PL 16,1116.]
As Liam suggested earlier, the Paschal Mystery is the foundation for this sacrament. Penance also relates closely to others aspects of the ministry of Christ’s presence. This root in Christ and connection with the other sacraments, especially Baptism and Eucharist, will be important to keep in mind.