Reconciliation

“I absolve you of your sins, in the name of the Father, and of the Son, and of the Holy Spirit.”

“Those who approach the sacrament of Penance obtain pardon from God’s mercy for the offense committed against him, and are, at the same time, reconciled with the Church which they have wounded by their sins and which by charity, by example, and by prayer labors for their conversion.”

Lumen Gentium 11 §2

Only God can forgive our sins. But Jesus willed that the Church should be his instrument of forgiveness on earth. On Easter night the Risen Christ imparted to his Apostles his own power to forgive sins. He breathed on them, imparting the promised Holy Spirit, and said, “Peace be with you.” Jesus was actually filling them with peace that is rooted in friendship with God. But he did more. He shared with them his own merciful mission. He breathed on them a second time and said, ” As the Father has sent me, so I send you. . . . Receive the holy Spirit. Whose sins you forgive are forgiven them, and whose sins you retain are retained.” (Jn 20:21-23)
That night Jesus gave the Church the ministry of the forgiveness of sins through the Apostles (cf. CCC, no. 1461). By the Sacrament of Holy Orders, bishops and priests continue this ministry to forgive sins “in the name of the Father, and of the Son, and of the Holy Spirit.” In this Sacrament, the priest acts in the person of Christ, the Head of the Church, to reconcile the sinner to both God and the Church. (US Catholic Catechism for Adults,  pg 236)