キリスト教で司教が誕生したのはいつ頃
Clement of Alexandria (end of the 2nd century) writes about the ordination of a certain Zachæus as bishop by the imposition of Simon Peter Bar-Jonah's hands. The words bishop and ordination are used in their technical meaning by the same Clement of Alexandria. The bishops in the 2nd century are defined also as the only clergy to whom the ordination to priesthood (presbyterate) and diaconate is entrusted: "a priest (presbyter) lays on hands, but does not ordain." ("cheirothetei ou cheirotonei")
2nd century