WHO CAN FORGIVE SINS?
Baptism, it is claimed, removes the guilt of “original sin” and of all sins committed up to that point. But according to Catholic theology, sins committed after baptism cannot be atoned for without the sacrament of penance (confession). “Penance is a sacrament of the New Law instituted by Christ in which forgiveness of sins committed after baptism is granted through the priest's absolution to those who with true sorrow confess their sins and promise to satisfy for the same… It comprises the actions of the penitent in presenting himself to the priest and accusing himself of his sins, and the actions of the priest in pronouncing absolution and imposing satisfaction.” According to Catholic theology, the priest does not simply assure the sinner that God has forgiven him, but actually grants the forgiveness, which is then “ratified” by God. “Christ not only declared that sins were forgiven, but really and actually forgave them; hence, the Apostles are empowered not merely to announce to the sinner that his sins are forgiven but to grant him forgiveness… If their power were limited to the declaration ‘God pardons you’, they would need a special revelation in each case to make the declaration valid.”
Since the priest himself is making the judgment, he must know the details of the sins in order to make an informed judgment. “How can a wise and prudent judgment be rendered if the priest be in ignorance of the cause on which judgment is pronounced? And how can he obtain the requisite knowledge unless it come from the spontaneous acknowledgment of the sinner… and the detailed confession of sins?”
Moreover, it is claimed that since God has established the sacrament of penance, this rules out the option of the sinner going directly to God to obtain forgiveness. “For those who after baptism have fallen into sin, the Sacrament of Penance is as necessary unto salvation as is baptism itself for those who have not yet been regenerated’ (Council of Trent, Sess. XIV, c. 2). Penance, therefore, is not an institution the use of which was left to the option of each sinner so that he might, if he preferred, hold aloof from the Church and secure forgiveness by some other means, e.g., by acknowledging his sin in the privacy of his own mind. The power granted by Christ to the Apostles is twofold, to forgive and to retain, in such a way that what they forgive God forgives and what they retain God retains. But this grant would be nullified if, in case the Church retained the sins of the penitent, he could, as it were, take appeal to God's tribunal and obtain pardon.... It would indeed have been strangely inconsistent if Christ in conferring this twofold power on the Apostles had intended to provide some other means of forgiveness such as confessing ‘to God alone'… By Divine ordinance the mercy of God can be obtained only through the supplications of the priests”. 
As in the other false doctrines that have been discussed, the real problem with the doctrine of priestly forgiveness is that the focus is on the sinner’s relationship with the priest, not with Christ. But Jesus expressed the desire of His heart in Matthew 11:28 when He said, “Come to Me, all you who labor and are heavy laden, and I will give you rest“.
 Catholic Encyclopedia article “Penance”.
 Catholic Encyclopedia article “Penance”.
 This and other Catholic doctrines are based upon “Holy Tradition” and can be traced to statements by the “fathers” such as Ignatius and Justin Martyr who wrote in the second century. However, there are at least three problems with relying on the “fathers” to provide information about the Apostolic church: 1) There is a time gap between the writings of the Apostles and those of the “fathers”. Paul, for example, was probably martyred around 67 AD, and had earlier said, “After my departure savage wolves will come in among you, not sparing the flock” (Acts 20:29). Peter warned, “There will be false teachers among you, who will secretly bring in destructive heresies” (2 Peter 2:1). The Bible writers who wrote later (Jude, Epistles of John) acknowledge that the corruption had already entered the church (e.g. “Contend earnestly for the faith which was once for all delivered to the saints. For certain men have crept in unnoticed, who long ago were marked out for this condemnation, ungodly men, who turn the grace of our God into lewdness and deny the only Lord God and our Lord Jesus Christ”, Jude 3,4, see also 1 John 2:18,19, 4:1,3 2 John 7-10). 2) That this corruption happened is evident from the dramatic differences between the theology of the Apostles and that of the “fathers”. Paul, for example, insists that we are made right and stay right with God because of what Jesus has done (Romans 5:10). In contrast, “According to Tertullian (one of the early “fathers”), ‘Exomologesis (penance) is the discipline which obliges a man to prostrate and humiliate himself and to adopt a manner of life that will draw down mercy. As regards dress and food, it prescribes that he shall lie in sackcloth and ashes, clothe his body in rags, plunge his soul in sorrow, correct his faults by harsh treatment of himself, use the plainest meat and drink for the sake of his soul and not of his belly: usually he shall nourish prayer by fasting, whole days and nights together he shall moan, and weep, and wail to the Lord his God, cast himself at the feet of the priests, fall on his knees before those who are dear to God, and beseech them to plead in his behalf". 3) The earliest writings, such as Ignatius, give evidence of having been tampered with so as to be in harmony with later Church doctrine.
 Catholic Encylopedia article “Penance”