When we say, “I believe in the forgiveness of sins,” we mean that we believe in the pardon, not only of original sin, but of all personal sins, mortal and venial.
Christ died for all men. By the infinite value of His sacrifice, the sin of Adam, which we inherit, is erased.
Jesus appeared to the Apostles on Easter Sunday evening and said, “Peace be with you” (John 20:19). “He showed them his hands and his side. Then the disciples were glad when they saw the Lord. Jesus said to them again, ‘Peace be with you. As the Father sent me, even so I send you.’ And when he had said this, he breathed on them, and said to them, ‘Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained’” (John 20:20-23). On this occasion Jesus instituted the Sacrament of Penance.
Then Jesus gave Peter and the other Apostles the power to forgive and retain sins. This power is given not only to the Apostles, but also to their lawful successors. When the Sacrament of Penance is administered, the very formula of absolution notes the role of the Holy Spirit in the forgiveness of sins.
Since the Apostles and their successors cannot acquire the necessary knowledge of sin unless the penitent himself gives it to them, Jesus demands a confession or an accusation of sins.
It is also true that a sinner can be restored to grace by perfect sorrow or perfect contrition. There are no sins, however serious, for which a repentant person cannot find forgiveness from God. A merciful Father has compassion on His children who want to love and serve Him.
Jesus appeared to the Apostles on Easter Sunday evening and said, “Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the
sins of any, they are retained” (John 20:22).
“‘Come now, let us reason together,’ says the Lord: ‘though your sins are like scarlet, they shall be as white as snow; though they are red like crimson, they shall become like wool’” (Isaiah 1:18).
“For the mountains may depart and the hills be removed, but my steadfast love shall not depart from you, and my covenant of peace shall not be removed, says the Lord, who has compassion on you” (Isaiah 54:10).
Jesus is the Lamb of God Who takes away the sins of the world. Our sins are washed away in His Blood: that Blood is offered to God in the Mass.
Certainly Christ did not take away the sins of future men unconditionally, but He provided the means by which our sins can be forgiven, as long as we cooperate with grace. We receive this particular grace through the Sacraments of Baptism and Penance.
Christ merited for us the benefits of His Redemption. He fully satisfied the justice of God for the infinite offense of sin; He freed mankind from its slavery; He made it possible for man to be united with God on earth by regaining for him the grace of divine life, that is, sanctifying grace. Thus man became an adopted son of God and an heir to Heaven.
The Catholic Church believes that sins forgiven are actually removed from the soul and not merely covered over by the merits of Christ. Only God can forgive sins, since He alone can restore sanctifying grace to a person who has sinned gravely and thereby lost the state of grace. God forgives the grave or mortal sins of the truly repentant sinner immediately through an act of perfect contrition or through a sacrament.
The sacraments primarily directed to the forgiveness of sins are Baptism and Penance, and secondarily, under certain conditions, the Sacrament of the Anointing of the Sick.