The Sacrament of Reconciliation or Confession is another symbolic action in which we encounter Christ and receive the reality of His grace. When we are sorry for having offended God, and seek to be reconciled to Him, we confess our sins to a priest who, as the representative of God (i.e. of Jesus, the Son of God), is able to give us God’s forgiveness and reconciliation.
Although it looks to one without faith as though we are confessing our sins only to another man, nevertheless we have faith that Jesus acts through the priest. And so, when the priest says “I absolve you”, Jesus Christ thereby absolves, that is, forgives your sins.
Only God forgives sins. Since he is the Son of God, Jesus says of himself, “The Son of man has authority on earth to forgive sins” and exercises this divine power: “Your sins are forgiven.” Further, by virtue of his divine authority he gives this power to men to exercise in his name.Catechism of the Catholic Church, 1441
Jesus gave the power to forgive sins to His Apostles.
(Jesus) said to them again, ‘Peace be with you. As the Father has sent me, so I send you.’ And when he had said this, he breathed on them and said to them, ‘Receive the holy Spirit. Whose sins you forgive are forgiven them, and whose sins you retain are retained.’John 20:21-23
The ability and authority to forgive sins has been handed on to the successors of the Apostles for the last 2000 years.
And all this is from God, who has reconciled us to himself through Christ and given us the ministry of reconciliation, namely, God was reconciling the world to himself in Christ, not counting their trespasses against them and entrusting to us the message of reconciliation.2 Corinthians 5:18-19
Therefore, confess your sins to one another and pray for one another, that you may be healed. The fervent prayer of a righteous person is very powerful.James 5: 16
An important part of the sacrament is the penance which the priest assigns; it is some sacrificial act or some prayers which help the sinner overcome the harmful effects, either to others or to himself, which the sin has caused.
Many sins wrong our neighbor. One must do what is possible in order to repair the harm (e.g., return stolen goods, restore the reputation of someone slandered, pay compensation for injuries). Simple justice requires as much. But sin also injures and weakens the sinner himself, as well as his relationships with God and neighbor. Absolution takes away sin, but it does not remedy all the disorders sin has caused. Raised up from sin, the sinner must still recover his full spiritual health by doing something more to make amends for the sin: he must “make satisfaction for” or “expiate” his sins. This satisfaction is also called “penance.”CCC, 1459
The harm done to one’s friendship with God is taken away when Christ, through the ministry of the priest, forgives the sins; the harm done to oneself or to society is repaired through the penance assigned by the priest.
But why do we confess? That is, why do we, in addition to being sorry for our sins, have to say them out loud? And to another person, a priest? Couldn’t we just tell God we are sorry, and he forgive us? Or have priests just forgive the sins of everyone before Mass?
Well, God could have set things up like this, I suppose. But it seems that he thinks it’s important to actually ask for forgiveness – to say our sins out loud and to say we are sorry.
What the Bible says is that Jesus wants priests to either forgive sins or retain them. Some sins, apparently, should not be forgiven, and some should. And so that the priest can know which ones to give absolution for, he has to hear them from the person seeking forgiveness, and so the that person has to confess them out loud.
Which sins should not be forgiven? you may ask. Shouldn’t a priest forgive every sin?
Well, no. Most basically, a priest should not forgive the sins a person is not truly sorry for, or which they do not intend to refrain from committing in the future. So, if in your confession you make it clear that you’re really not sorry or that you intend to continue committing adultery or stealing, a priest cannot forgive those sins; he should retain them.
But also, certain especially serious and public sins, like public renunciation of the faith, physically assaulting the pope or breaking the seal of confession, only the pope can forgive.
When Jesus died for the sins of all mankind, it is not that God automatically, preemptively forgives each personal future sin so that no one needs to repent of them. If that were the case, all people everywhere would already be reconciled to God – no personal faith or repentance would ever be necessary to receive God’s gift of himself in Heaven. On the cross, Jesus gave access to the Father’s forgiveness – and that access is not made possible without Jesus’ sacrifice – but the forgiveness has to be applied to us whenever we, through our sins, have need of it.
The Bible makes clear that faith and repentance are necessary throughout our life, that Christians sometimes still commit serious sin, and we need to repeatedly ask for forgiveness in order to persevere to final salvation.
Jesus instituted the Sacrament of Reconciliation, whereby priests continue to apply the forgiveness won through his death on the cross to the actual sins of his future followers, Christians down through the ages.
So confession and the Sacrament of Reconciliation is a great source of God’s grace and the loving care he shows to us while we are still sinners, to bring us back into friendship with him and to strengthen us to persevere in that friendship.