John 20:21-23 Jesus therefore said to them again, Peace be unto you: as the Father hath sent me, even so send I you. 22 And when he had said this, he breathed on them, and saith unto them, Receive ye the Holy Spirit: 23 whose soever sins ye forgive, they are forgiven unto them; whose soever sins ye retain, they are retained.
Matthew 9:2-8 And behold, they brought to him a man sick of the palsy, lying on a bed: and Jesus seeing their faith said unto the sick of the palsy, Son, be of good cheer; thy sins are forgiven. 3 And behold, certain of the scribes said within themselves, This man blasphemeth. 4 And Jesus knowing their thoughts said, Wherefore think ye evil in your hearts? 5 For which is easier, to say, Thy sins are forgiven; or to say, Arise, and walk? 6 But that ye may know that the Son of man hath authority on earth to forgive sins (then saith he to the sick of the palsy), Arise, and take up thy bed, and go up unto thy house. 7 And he arose, and departed to his house. 8 But when the multitudes saw it, they were afraid, and glorified God, who had given such authority unto men.
Isaiah 43:25 I, even I, am he that blotteth out thy transgressions for mine own sake; and I will not remember thy sins.
Luke 5:21 And the scribes and the Pharisees began to reason, saying, Who is this that speaketh blasphemies? Who can forgive sins, but God alone?
Luke 6:37 And judge not, and ye shall not be judged: and condemn not, and ye shall not be condemned: release, and ye shall be released.
2 Corinthians 5:18-19 But all things are of God, who reconciled us to himself through Christ, and gave unto us the ministry of reconciliation; 19 to wit, that God was in Christ reconciling the world unto himself, not reckoning unto them their trespasses, and having committed unto us the word of reconciliation.
1 John 2:12 I write unto you, my little children, because your sins are forgiven you for his name's sake.
Colossians 3:13 Forbearing one another, and forgiving each other, if any man have a complaint against any; even as the Lord forgave you, so also do ye.
Luke 24:45-47 Then opened he their mind, that they might understand the scriptures; 46 and he said unto them, Thus it is written, that the Christ should suffer, and rise again from the dead the third day; 47 and that repentance and remission of sins should be preached in his name unto all the nations, beginning from Jerusalem.
Only God can forgive sins (Is. 43:25, Luke 5:21). This fact was generally accepted in the Jewish society. That is why, when Jesus forgave sins of the man sick of the palsy, the minds of the scribes minds reacted so sharply (Matt. 9:2-8). Why did Jesus do that? He did it to show that he was not an ordinary man, but God, the only one to have the power to forgive sins. To prove it, he used the very same power to heal this man. No one should conclude that every person can forgive sins likewise.
So, how should we understand John 20:21-23, when Jesus is giving instructions to his disciples: "whose soever sins ye forgive, they are forgiven unto them; whose soever sins ye retain, they are retained."? At the first sight, it might seem to mean that Jesus gave them power to forgive one's sins and, in other words, to decide about their life or death. But is this impression correct?
Absolutely not!
A couple years later, John wrote: "I write unto you, my little children, because your sins are forgiven you for his name's sake..." (1J.2:12). Here, he clearly states the sins are forgiven "for his name". In 2 Co 5:18-19, Pauls says the God gave unto us the ministry of reconsiliation. In other words, our ministry is to tell people that it's possible (and necessary) to gain the forgiveness of sins and that they can achieve that through the reconsiliation with God, accepting the sacrifice of Jesus's blood. The apostles and other disciples weren't forgiving the sins (2 Cor. 5:18, Luke 23:45-47), but fulfilling this ministry of reconsiliation. There is no such a place in Bible that would suggest that God has given a human such a prerogative competence like the power to forgive sins.
No man can foregive sins and everyone, who claims the oposite, acts against the Scriptures and causes damage to people, who rely on this ability. If people really had power to forgive sins, it'd cause an unhealthy business with human desire for the eternal life. God however knows us and he knows that a human would not be able to avoid misusing it. That is why, the interpretation of John, chapter 20, that Jesus gave the real power over life and death to his disciples, is purpose-built and totally wrong.
The real forgiveness of sins is bound to Jesus Christ's shed blood and to the forgiveness of people between each other (Col. 3:13, Luke 6:37, etc.). The Scriptures say that we need to forgive each other, which means that we can and we should decide about the guilt of other people against ourselves. However, this is something completely different from when God forgives their sins. About the sins in the relationship between God and a human, only God can decide whether he forgives them or not. Therefore only he is the one that we should ask for forgiveness and expect it.
The instruction that Jesus was giving to his disciples / to the church, was to bring the good news about how forgiveness of sins can be achieved and what it means to the person. This is the power to "forgive or retain their sins" as mentioned in John, chapter 20. Whether they preach what they should and whether they maintain faithful to the Bible or not.
