“Those who approach the sacrament of Penance obtain pardon from God’s mercy for the offense committed against Him, and are, at the same time, reconciled with the Church which they have wounded by their sins and which by charity, by example, and by prayer labors for their conversion.” CCC 1422
“Why can’t I just confess my sins to God?” One of the strangest truths about God is that He shares what is properly His with human beings. He worked through Moses to liberate Israel from slavery, He used the prophets to proclaim His word, and in confession, He works through priests to forgive our sins. Saint Paul considers himself to be a steward of the mysteries of God (1 Corinthians 4:1); and even goes so far as to say that God gave to him and others the “ministry of reconciliation” (2 Corinthians 5:18). In other words, God works through people, He reaches us through others, and He gives authority to certain ministers in the church – namely priests. Jesus gave the apostles (the first priests) the authority to forgive sins (John 20:21-23) and that gift has been alive in the Church ever since.
Confessing our sins out loud to another human being is good for us. The chief sin of mankind is pride, and confession is humbling – which is a good thing. There is also such a grace and joy to hearing a priest pray the words of mercy: “May God give you pardon and peace, and I absolve you of your sins in the name of the Father, and of the Son, and of the Holy Spirit.”