“It is not lawful to baptize or give communion without the consent of the bishop.” (Letter to Smyrnaeans)
“Take care to do all things in harmony with God, with the bishop presiding in the place of God, and with the presbyters in the place of the council of the apostles, and with the deacons” (Letter to Magnesians)
Titus was entrusted with the duty of appointing elders or presbyters in every town in Crete (1:5). The word “bishop” isn’t used in this context, but whatever Titus’ title was, he was clearly placed in authority over a large number of local churches.
Read the Acts of the Apostles. There’s an enormous distinction between Apostles and other Christians; the fact that they elected another to replace Judas meant the apostolic office was intended to go on.
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