Already taken care of at the Cross
9For in Him all the fullness of Deity dwells in bodily form,
10and in Him you have been made complete, and He is the head over all rule and authority;
11and in Him you were also circumcised with a circumcision made without hands, in the removal of the body of the flesh by the circumcision of Christ;
12having been buried with Him in baptism, in which you were also raised up with Him through faith in the working of God, who raised Him from the dead.
13When you were dead in your transgressions and the uncircumcision of your flesh, He made you alive together with Him, having forgiven us all our transgressions,
14having canceled out the certificate of debt consisting of decrees against us, which was hostile to us; and He has taken it out of the way, having nailed it to the cross.
Colossians 2:9-14 NASB
Confessing our sins is very important to the Christian life. First because it makes us realize how much we need a savior. Second, simply because Scripture tells us to do so.
The problem comes when it gets turned into a work that has to be done in order to have salvation, when the Apostle says that we are saved by grace through faith, and not by works.
I’ve heard Catholics who have told me in snooty voices, “Unlike you, I’VE gone to Confession and gotten my sins forgiven!” Like they’ve done something really great that us lesser mortals can only aspire to. That’s the exact opposite of what the Lord teaches!