If Christians confess their sins directly to God why did Jesus give the sacrament of penance?

On the first Easter Sunday, Jesus appeared to His Apostles, "breathed on them," and said, "'Receive the Holy Spirit. If you forgive men's sins, they are forgiven them; if you hold them bound, they are held bound.'" (John 20:21-23) Beyond this account of the Lord Jesus' institution of the Sacrament of Penance, Scripture does not give us His reasons for doing as He did. We do know that the Jesus is infinite love and mercy, and that anything He chose to do during His time on Earth, He must have done because of His great love for us and because of the infinite mercy He has in His heart towards us. Knowing you have done something wrong is a miserable feeling. Police detectives know that, if they wait long enough, a criminal who is not entirely a lost soul - who still has a conscience - will sooner or later confess to his crime. It's not necessary for the police to "rough up" or "give the business to" any but hardened criminals; most people with a conscience are bothered when they have done something wrong, and feel the need to tell somebody. Shakespeare wrote, "Conscience doth make cowards of us all." (Hamlet, Act III, sc 1) It is true that we confess our sins to God, but the Catholic Church teaches that when we sin, we sin against the entire body of Christ, which is the Church, and we must be reconciled with God and with our neighbor through the Church. This is one of the things the Sacrament of Penance does: it allows the penitent to "get it off his chest", and at the same time, through the ministry of the priest, allows him to become reconciled not only with God, but with the entire Church. The priests are specially trained to help sinners with their burdens. Sometimes, a young man or a young woman may believe that they are truly repentant, but there may be in the back of their minds a certain cavalier attitude of "so what? Everyone's doing it." If this be the case, then the sinner's heart is not sincerely repentant. We know that God will not be mocked. On hearing this person's confession, the priest may ask some gentle questions and pose some hard truths intended to cause the penitent to wake up and really see the sin in what he or she had been doing for what it is. This is an inestimable grace of the Sacrament. Similarly, there may be penitents who are troubled with all manner of faults and failings and weigh themselves down with imagined sins that really aren't there at all. Priests are trained also to deal gently and considerately with souls in need of comfort and compassion, and will put their minds at ease about the state of their soul. The more I think of all the wonderful benefits of the Sacrament of Penance, the more I think to myself how very wise Our Lord Jesus is!