The context of John 20:23 is that Jesus was speaking to the disciples (v. 19). He breathed on them to receive the Holy Spirit (v. 22). There is nothing in here about priests having the authority to forgive sins. There is nothing here (or anywhere else in the New Testament) about apostolic succession that says priests have the authority to forgive sins and that it is passed down. The Bible does mention appointing elders (Acts 14:23; Titus 1:5), and that the disciples of Jesus had special authority (Matt. 16:18).
It speaks of the laying on of hands to receive the Holy Spirit (Acts 8:19) as well as ordaining men to the ministry (1 Tim. 4:14; 2 Tim. 1:6; Titus 1:5). At best, the laying on of hands deals with ordination--not apostolic authority being passed down. After all, they were ordaining elders and not apostles; and it was the apostles who were given the authority by Christ to do miracles and write scripture. Nothing is said here about apostolic authority being passed down.
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It speaks of the laying on of hands to receive the Holy Spirit (Acts 8:19) as well as ordaining men to the ministry (1 Tim. 4:14; 2 Tim. 1:6; Titus 1:5). At best, the laying on of hands deals with ordination--not apostolic authority being passed down. After all, they were ordaining elders and not apostles; and it was the apostles who were given the authority by Christ to do miracles and write scripture. Nothing is said here about apostolic authority being passed down.
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Judas was replaced by Matthias so you have apostolic succession right there. Why would the authority to forgive sins not be passed down?