God alone forgives, God alone give power to forgive
Truth: Only God ultimately forgives sins. His is the prerogative and power. However, his also is the power to delegate this authority to man. This is what he has done through Christ.
So Jesus said to them again, “Peace be with you; as the Father has sent Me, I also 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, their sins have been forgiven them; if you retain the sins of any, they have been retained.’- JOHN 20:22-23
This definitely points to their new authority to forgive sins. However, they wouldn’t know which to forgive and which to retain unless they first hear them.
Again, what did Christ say to them? “as the Father sent me”, how did the Father send him? : With “authority on earth to forgive sins”. (Matthew 9).
This is simple:
The Father sent the Son, anointed him with the Holy Spirit, and gave him power to forgive sins thereby saving the world through the merits of his Passion and Death. Christ too gathers his Apostles, sends them out “as the Father” did, breathed on them and gave them the same anointing, with the same power to forgive sins, thereby ministering redemption in his name to the world. The mission of Christ is to save the world and the mission of the Apostles is to save the world by ministering salvation to all in the name of Christ.
In another passage Christ gives Peter and by extension the other Apostles the Keys to the Kingdom of heaven, and I dare say, an arbitrary power to bind and loose on earth and in heaven. This power is clearly Divine. If it were only to “loose on earth”, it would be ordinary, but add “loosed in heaven” and we have something otherworldly in our hands.
Christ is the Image of the Father, He inherits all His power and authority as Son.
All authority has been given to Me in heaven and on earth. “Go therefore and make disciples of all the nations, baptizing them in the name of the Father and the Son and the Holy Spirit. – Matthew 28:18-19
We are Christ’s image, members of his body and co-heirs of Heaven. We also as a Community inherit his authority to teach and speak in his name, to free the captives and to set prisoners free (sin). This authority however is proper to priests and Bishops who have inherited the ministerial priesthood of Christ through Apostolic Succession, meaning that each Bishop can trace his lineage back to St Peter and the Apostles. To break it even further: each Bishop has been ordained by someone who’s been ordained by someone who’s been ordained by the Apostles.
The Bible tells us to confess our sins to one another (James James 5:16) In this context of this verse, a person is told to “summon the presbyters of the church” (James 5:14). Presbyter is the Greek word for priest.
Christ wants all of his works continued not some
Christ wants the Apostles to never stop doing everything he did. He wanted them to continue ALL OF HIS WORKS till the end of the world. That is why he charged them, commissioned them, anointed and empowered them with divine authority to continue his saving work.
Baptism is one of those divine works. In this a person’s sins is totally wiped off, he becomes as clean as an Angel. This is clearly also “forgiveness of sins”, granted by God through the mediation of man. If you think about it, it is kind of a bigger miracle than confession which only forgives guilt but does not always remove every temporary punishment due to those sins.
Also since sin is not only an offence against God but also against the Church, the Body of Christ, confession is also a celebration of reconciliation with the Church as well. The priest represents both Christ freeing the penitent and the Church welcoming him back into the fold.
For your mortal sins, you can talk to God directly, however you must receive sacramental pardon for it to be complete. So, no, you cannot exclude the priest from the equation.