[MSKKG]

I'm an Orthodox Christian. In regard to the Sacrament of Confession, here is a paraphrase of what the Church says: God alone forgives sin. Jesus (God the Son) forgave sins and gave His apostles the power to remit or retain sins (cf. John 20:23). In the early Church, the sinner had to confess before the entire congregation! As the Church grew, the practice of privately confessing to the priest developed--he kind of represented the congregation.

Concerning Mary and intercessory prayers, here is a direct quote from The Faith by Clark Carlton (sorry for the length):

"While our Lord was hanging from the Cross, pouring out His life for the salvation of the world, He looked down upon His most pure Mother and the Apostle John and said to the holy Virgin,
"Woman, behold thy son." To John He said, "Behold thy mother" (John 19:26-27). From this time forth, the Virgin maiden who had given birth to God in the flesh was to be the mother of His Disciples. Just as Eve was the "Mother of all the living," so the Virgin is the "Mother of all Christians," the personification of Holy Mother Church. To those who are united to her Son through Holy Baptism, she extends her motherly embrace.

"As our Mother, the All-holy Theotokos intercedes for us before the Throne of Her Son. As our fervent Intercessor and constant Advocate before the Creator, the Virgin never tires and never fails to remember her spiritual children in her prayers. When we are at our lowest ebb and feel as though we have been forsaken by all the world, we may take courage in the fact that our Lady is ever ready to come to us and intercede for us, winning greater strength for all who call upon her Son in faith.

"Since the time of the Protestant Reformation, however, much of Western Christendom has either ignored or rejected outright the intercession of the Mother of God and the Saints for those on earth. In doing so, Protestants have forfeited one of the greatest privileges of being Christians. The Apostle James enjoins us to pray for one another, and in the same verse, explains why: the effectual fervent prayer of a righteous man availeth much (James 5:16). It is ironic that those who oppose the idea of seeking the intercession of the Saints in heaven have no objections to asking ordinary, sinful Christians to pray for them. But let us consider whose prayers, according to St. James, are more effectual: those Christians still alive on earth struggling with their own sins and problems, or those who have gone on to be with God and are recognized by the Church for their holiness of life?

"The Saints are those who have passed through this life in victorious faith and now behold the face of Christ. United with Him in love, they exist in a state of perfect accord with His holy will. Thus, we may be assured that when they pray for us who are on earth, their supplications are in complete harmony with the purposes of God. No longer capable of being deceived by the wiles of the devil, they form a mighty army, joining their will to the will of God and standing firm with us as we fight the good fight of faith. If God hears the prayers of ordinary Christians embroiled in the trials of life (and He certainly does), then how much more does He heed the intercessions of those who have pleased Him most, whom He has called to be with Himself in heaven.

"I am the God of Abraham, and the God of Isaac, and the God of Jacob. God is not the God of the dead, but of the living (Matthew 22:32). In Christ, death is no longer the impenetrable barrier which separates us from those who have gone on before us. Indeed, the writer of Hebrews affirms that the Saints in heaven are aware of what is going on in our lives:

"Wherefore seeing we also are compassed about with so great a cloud of witnesses, let us lay aside every weight, and the sin which doth so easily beset us, and let us run with patience the race that is set before us (Hebrews 12:1).

"The Saints not only cheer us on as we run the race of life, they actively participate in our race as they intercede for us, winning greater strength for all who battle evil. Our All-holy Lady, the Theotokos, stands at the head of this chorus of Saints and remains for us on earth our steadfast Protectress and constant Advocate before the Creator . . . ."