Christ gave the power to forgive sins to the Church he established.
On the evening of that first day of the week, when the disciples were together, with the doors locked for fear of the Jews, Jesus came and stood among them and said, Peace be with you! After he said this, he showed them his hands and side. The disciples were overjoyed when they saw the Lord. Again Jesus said, Peace be with you! As the Father has sent me, I am sending you. And with that he breathed on them and said, Receive the Holy Spirit. If you forgive anyone his sins, they are forgiven; if you do not forgive them, they are not forgiven. John 20:19-23
Look at the phrase he breathed on them. There is only one other place in the Bible where God breathes on man the LORD God formed the man from the dust of the ground and breathed into his nostrils the breath of life, and the man became a living being. Genesis 2:7 So, from Scripture alone, you can see that something special is going on here. And then look at the next part - Receive the Holy Spirit. If you forgive anyone his sins, they are forgiven; if you do not forgive them, they are not forgiven. Christ is giving certain men the power to forgive sins. The only way they could know if a sin is to be forgiven or retained is to Hear It. At that point Christ instituted, in the Church he created with with his priesthood, the sacrament of Penance, or confession.
I'm speechless!