Reconciliation offers us the opportunity to repair our relationship with God when we damage it with sin. The grace offered through this post-baptismal Sacrament of Healing enables us to receive the graces of other sacraments by restoring us to a “state of grace.”
We are called to be one people united with Christ and one another. Sadly, in our weakness this unity is often ruptured through failures to love (i.e. we sin). Yet God's love for us does not cease when we fail. In this Sacrament, through the Ministry of the Priest, God forgives the sins of those who confess them and reconciles them to Himself and the whole Christian Community. By expressing our sorrow for our sin in the Sacrament of Penance or Reconciliation, we experience forgiveness and healing. Our relationship with God and our unity as Church is made whole again.
Source: Catechism of the Catholic Church