About the middle of the third century various circumstances conspired to augment the authority of the great bishops.  In the Decian and Valerian persecutions the chief pastors were specially marked out for attack, and the heroic constancy with which some of the most eminent encountered a cruel death vastly enhanced the reputation of their order.  In a few years several bishops of Rome were martyred; Cyprian of Carthage endured the same fate:  Alexander of Jerusalem, and Babylas of Antioch, also laid down their lives for their religion. [600:1] At the same time the schism of Novatian at Rome, and the schism of Felicissimus at Carthage threatened the Church with new divisions, and the same arguments which were used, upwards of a hundred years before, for increasing the power of the president of the eldership, could now be urged with equal pertinency for adding to the authority of the president of the synod.  In point of fact perhaps the earliest occasion on which the bishop of Rome executed discipline in his archiepiscopal capacity was immediately connected with the schism of Novatian; for we have no record of any exercise of such power until Cornelius, at the head of a council held in the Imperial city, deposed the pastors who had officiated at the consecration of his rival. [601:1] From this date the Roman metropolitan probably presided at all the ordinations of the bishops in his vicinity.

To prevent the recurrence of schisms such as had now happened at Rome and Carthage, it was, in all likelihood, arranged about this period, at least in some quarters of the Church, that the presence or sanction of the stated president of the provincial synod should be necessary to the validity of all episcopal consecrations.  There were still, however, many districts in which the provincial synod had no fixed chairman.  Hence an ancient canon directs that at the ordination of a member of the hierarchy, “one of the principal bishops shall pray to God over the approved candidate.” [601:2] By a “principal bishop” we are to understand the chief pastor of a principal or apostolic church; [601:3] but in some provinces several such churches were to be found, and this regulation attests that there no single ecclesiastic had yet acquired an unchallenged precedence.  As the close of the third century approached, the ecclesiastical structure exhibited increasing uniformity; and one dignitary in each region began to be known as the stated president of the episcopal body.  In one of the so-called apostolical canons, framed probably before the Council of Nice, this arrangement is embodied.  “The bishops of every nation,” says the ordinance, “ought to know who is the first among them, and him they ought to esteem as their head, and not do any great thing without his consent. ...  But neither let him do anything without the consent of all.” [602:1]