“And with that he breathed on them and said, “Receive the Holy Spirit. If you forgive anyone’s sins, their sins are forgiven; if you do not forgive them, they are not forgiven.” John 20 : 22-23
The Sacrament of Reconciliation (or Penance) is when God through the priest forgives a person for their sins. Through this we are able to open our hearts to God - who through his love, compassion and mercy, desires to free us from the burden of sin by His forgiveness mediated through the Priest and to fill us with his peace.