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As the Church continued to expand, new churches in important cities gained their own bishop.Churches in the regions outside an important city were served by Chorbishop, an official rank of bishops.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) At the beginning of the 3rd century, Hippolytus of Rome describes another feature of the ministry of a bishop, which is that of the "Spiritum primatus sacerdotii habere potestatem dimittere peccata": the primate of sacrificial priesthood and the power to forgive sins.
Early sources are unclear but various groups of Christian communities may have had the bishop surrounded by a group or college functioning as leaders of the local churches.
In Timothy and Titus in the New Testament a more clearly defined episcopate can be seen.
We are told that Paul had left Timothy in Ephesus and Titus in Crete to oversee the local church (1Tim 1:3 and Titus 1:5).
"Therefore as the Lord did nothing without the Father, [being united with Him], either by Himself or by the Apostles, so neither do ye anything without the bishop and the presbyters." — Epistle of Ignatius to the Magnesians 7:1.
"Be obedient to the bishop and to one another, as Jesus Christ was to the Father [according to the flesh], and as the Apostles were to Christ and to the Father, that there may be union both of flesh and of spirit." — Epistle of Ignatius to the Magnesians 13:2.