A question of no small importance arose at that time. For the parishes of all Asia, as from an older tradition, held that the fourteenth day of the moon, when the Jews were commanded to sacrifice the lamb, should be observed as the feast of the Saviour’s passover, on which day they should end their fast, whatever day of the week it should be. But the churches in the rest of the world observed the practice which, from apostolic tradition, has prevailed to the present time, of terminating the fast on no other day than on that of the resurrection of our Saviour.
Synods and assemblies of bishops were held on this account, and all, with one consent, through mutual correspondence drew up an ecclesiastical decree, that the mystery of the resurrection of the Lord should be celebrated on no other but the Lord’s day, and that we should observe the close of the paschal fast on this day only. There is still extant a writing of those who were then assembled in Palestine, over whom Theophilus, bishop of Cæsarea, and Narcissus, bishop of Jerusalem, presided. And there is another of those assembled at Rome, which bears the name of Bishop Victor; also of the bishops in Pontus over whom Palmas, as the oldest, presided; and of the parishes in Gaul of which Irenæus was bishop, and of those in Osrhoëne and the cities there; and a personal letter of Bacchylus, bishop of the church at Corinth, and of a great many others, who uttered the same opinion and judgment, and cast the same vote.
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But the bishops of Asia, led by Polycrates, decided to hold to the old custom handed down to them. In a letter addressed to Victor and the church of Rome, he set forth the tradition: “We observe the exact day; neither adding, nor taking away. For in Asia also great lights have fallen asleep, … Among these are Philip, one of the twelve apostles, who fell asleep in Hierapolis; … and John, who was both a witness and a teacher, who reclined upon the bosom of the Lord, and, being a priest, wore the sacerdotal plate. He fell asleep at Ephesus. And Polycarp in Smyrna, who was a bishop and martyr; and Thraseas, bishop and martyr from Eumenia, who fell asleep in Smyrna… All these observed the fourteenth day of the passover according to the Gospel, deviating in no respect, but following the rule of faith. And I also, Polycrates, the least of you all, do according to the tradition of my relatives, seven of whom were bishops; and I am the eighth … For those greater than I have said ‘We ought to obey God rather than man.'”
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Thereupon Victor, who presided over the church at Rome, immediately attempted to cut off from the common unity the parishes of all Asia, with the churches that agreed with them, as heterodox; and he wrote letters and declared all the brethren there wholly excommunicate. But this did not please all the bishops. And they besought him to consider the things of peace, and of neighborly unity and love. Words of theirs are extant, sharply rebuking Victor.
Among them was Irenæus, who, sending letters in the name of the brethren in Gaul over whom he presided, maintained that the mystery of the resurrection of the Lord should be observed only on the Lord’s day. He fittingly admonishes Victor that he should not cut off whole churches of God which observed the tradition of an ancient custom. “When the blessed Polycarp was at Rome in the time of Anicetus, and they disagreed a little about certain other things, they immediately made peace with one another, not caring to quarrel over this matter. For neither could Anicetus persuade Polycarp not to observe what he had always observed with John the disciple of our Lord, and the other apostles with whom he had associated; neither could Polycarp persuade Anicetus to observe it as he said that he ought to follow the customs of the presbyters that had preceded him. But though matters were in this shape, they communed together, and Anicetus conceded the administration of the eucharist in the church to Polycarp, manifestly as a mark of respect. And they parted from each other in peace, both those who observed, and those who did not, maintaining the peace of the whole church.” Thus Irenæus, who truly was well named, became a peacemaker in this matter, exhorting and negotiating in this way in behalf of the peace of the churches.
— Eusebius Pamphilius: Church History. V.XXIII-XXV. NPNF201.