Cyprian to Antonian, his brother. Greeting … You wrote … that I should forward a copy of the same letter to our colleague [Pope] Cornelius, so that, laying aside all anxiety, he might at once know that you held communion with him, that is, with the Catholic Church. ibid., 55[52]:1

With a false bishop appointed for themselves by heretics, they dare even to set sail and carry letters from schismatics and blasphemers to the chair of Peter and to the principal church [at Rome], in which sacerdotal unity has its source. ibid., 59:14

Firmilian, d. c. 269 AD

[Pope] Stephen … boasts of the place of his episcopate, and contends that he holds the succession from Peter, on whom the foundations of the Church were laid [Matt. 16:18]. … Stephen … announces that he holds by succession the throne of Peter. collected in Cyprian’s Letters 74[75]:17 [A.D. 253]

Eusebius of Caesarea, d. 30 May 339 AD

And when a dissension arose about these said people [the Montanists], the brethren in Gaul once more . . . [sent letters] to the brethren in Asia and Phrygia and, moreover to Eleutherius, who was then [A.D. 175] bishop of the Romans, negotiating for the peace of the churches. Church History 5:3:4 [A.D. 312]

And the same martyrs too commended Irenaeus, already at that time [A.D. 175] a presbyter of the community of Lyons, to the said bishop of Rome, rendering abundant testimony to the man, as the following expressions show: ‘Once more and always we pray that you may rejoice in God, Pope Eleutherius. This letter we have charged our brother and companion Irenaeus to convey to you, and we beg you to receive him as zealous for the covenant of Christ’. ibid., 5:4:1–2

[Regarding the Pascha (Easter) controversy of 190 AD] Thereupon [Pope] Victor, who presided over the church at Rome, immediately attempted to cut off from the community the parishes of all Asia [Minor], 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. . . . [Irenaeus] fittingly admonishes Victor that he should not cut off whole churches of God which observed the tradition of an ancient custom. ibid., 5:23:1–24:11

Thus then did Irenaeus entreat and negotiate [with Pope Victor] on behalf of the peace of the churches—[Irenaeus being] a man well-named, for he was a peacemaker both in name and character. And he corresponded by letter not only with Victor, but also with very many and various rulers of churches. ibid., 24:18

St. Cyril of Jerusalem, d. 386 AD

The Lord is loving toward men, swift to pardon but slow to punish. Let no man despair of his own salvation. Peter, the first and foremost of the apostles, denied the Lord three times before a little servant girl, but he repented and wept bitterly Catechetical Lectures 2:19 [A.D. 350]

[Simon Magus] so deceived the city of Rome that Claudius erected a statue of him. . . . While the error was extending itself, Peter and Paul arrived, a noble pair and the rulers of the Church, and they set the error aright. . . . [T]hey launched the weapon of their like-mindedness in prayer against the Magus, and struck him down to earth. It was marvelous enough, and yet no marvel at all, for Peter was there—he that carries about the keys of heaven [Matt. 16:19]. ibid., 6:14

In the power of the same Holy Spirit, Peter, both the chief of the apostles and the keeper of the keys of the kingdom of heaven, in the name of Christ healed Aeneas the paralytic at Lydda, which is now called Diospolis [Acts 9:32–34]. ibid., 17:27

St. Ephrem the Syrian, d. 373 AD

[Jesus said:] Simon, my follower, I have made you the foundation of the holy Church. I betimes called you Peter, because you will support all its buildings. You are the inspector of those who will build on Earth a Church for me. If they should wish to build what is false, you, the foundation, will condemn them. You are the head of the fountain from which my teaching flows; you are the chief of my disciples. Through you I will give drink to all peoples. Yours is that life-giving sweetness which I dispense. I have chosen you to be, as it were, the firstborn in my institution so that, as the heir, you may be executor of my treasures. I have given you the keys of my kingdom. Behold, I have given you authority over all my treasures. Homilies 4:1 [A.D. 351]

St. Athanasius of Alexandria, d. 2 May 373 AD

If any bishop loses the judgment in some case [decided by his fellow bishops] and still believes that he has not a bad but a good case, in order that the case may be judged anew…let us honor the memory of the Apostle Peter by having those who have given the judgment write to Julius, Bishop of Rome, so that if it seem proper he may himself send arbiters and the judgment may be made again by the bishops of a neighboring province. Council of Sardica, Canon 3, [A.D.342]

When I left Alexandria, I did not go to your brother’s headquarters, or to any other persons, but only to Rome; and having laid my case before the Church (for this was my only concern), I spent my time in public worship. Defence before Constantius 4, NPNF 2, Vol. IV, 239 [A.D. 356]

Rome is called “the Apostolic throne.” Athanasius, Hist. Arian, ad Monach. n. 35 [A.D. 362]

Pope St. Damasus I, d. 11 December 384 AD

Likewise it is decreed . . . that it ought to be announced that . . . the holy Roman Church has been placed at the forefront not by the conciliar decisions of other churches, but has received the primacy by the evangelic voice of our Lord and Savior, who says: ‘You are Peter, and upon this rock I will build my Church, and the gates of hell will not prevail against it; and I will give to you the keys of the kingdom of heaven . . . ’ [Matt. 16:18–19]. The first see, therefore, is that of Peter the apostle, that of the Roman Church, which has neither stain nor blemish nor anything like it. Decree of Damasus 3 [A.D. 382]

St. Jerome, d. 30 September 420 AD

‘But,’ you [Jovinian] will say, ‘it was on Peter that the Church was founded’ [Matt. 16:18]. Well . . . one among the twelve is chosen to be their head in order to remove any occasion for division. Against Jovinian 1:26 [A.D. 393]

Pope St. Innocent I, d. 12 March 417 AD

In seeking the things of God . . . you have acknowledged that judgment is to be referred to us [the pope], and have shown that you know that is owed to the Apostolic See [Rome], if all of us placed in this position are to desire to follow the apostle himself [Peter] from whom the episcopate itself and the total authority of this name have emerged. Letters 29:1 [A.D. 408]

St. Augustine. d. 28 August 430 AD

Among these [apostles] Peter alone almost everywhere deserved to represent the whole Church. Because of that representation of the Church, which only he bore, he deserved to hear ‘I will give to you the keys of the kingdom of heaven’. Sermons 295:2 [A.D. 411]

Some things are said which seem to relate especially to the apostle Peter, and yet are not clear in their meaning unless referred to the Church, which he is acknowledged to have represented in a figure on account of the primacy which he bore among the disciples. Such is ‘I will give unto you the keys of the kingdom of heaven,’ and other similar passages. Commentary on Psalm 108 1 [A.D. 415]

Who is ignorant that the first of the apostles is the most blessed Peter? Commentary on John 56:1 [A.D. 416]

Council of Ephesus, 431 AD

Philip, presbyter and legate of [Pope Celestine I] said: ‘We offer our thanks to the holy and venerable synod, that when the writings of our holy and blessed pope had been read to you . . . you joined yourselves to the holy head also by your holy acclamations. For your blessedness is not ignorant that the head of the whole faith, the head of the apostles, is blessed Peter the apostle’. Acts of the Council, session 2 [A.D. 431]

Philip, the presbyter and legate of the Apostolic See [Rome] said: ‘There is no doubt, and in fact it has been known in all ages, that the holy and most blessed Peter, prince and head of the apostles, pillar of the faith, and foundation of the Catholic Church, received the keys of the kingdom from our Lord Jesus Christ, the Savior and Redeemer of the human race, and that to him was given the power of loosing and binding sins: who down even to today and forever both lives and judges in his successors’. ibid., session 3

Pope St. Leo the Great, d. 10 November 461 AD

Our Lord Jesus Christ . . . has placed the principal charge on the blessed Peter, chief of all the apostles, and from him as from the head wishes his gifts to flow to all the body, so that anyone who dares to secede from Peter’s solid rock may understand that he has no part or lot in the divine mystery. He wished him who had been received into partnership in his undivided unity to be named what he himself was, when he said: ‘You are Peter, and upon this rock I will build my Church’ [Matt. 16:18]. Letters 10:1 [A.D. 445]

Our Lord Jesus Christ . . . established the worship belonging to the divine [Christian] religion. . . . But the Lord desired that the sacrament of this gift should pertain to all the apostles in such a way that it might be found principally in the most blessed Peter, the highest of all the apostles. And he wanted his gifts to flow into the entire body from Peter himself, as if from the head, in such a way that anyone who had dared to separate himself from the solidarity of Peter would realize that he was himself no longer a sharer in the divine mystery. ibid., 10:2–3

Although bishops have a common dignity, they are not all of the same rank. Even among the most blessed apostles, though they were alike in honor, there was a certain distinction of power. All were equal in being chosen, but it was given to one to be preeminent over the others. . . . [So today through the bishops] the care of the universal Church would converge in the one See of Peter, and nothing should ever be at odds with this head. ibid., 14:11

Pope St. Hormisdas, d. 6 August 523 AD

The Formula of Hormisdas settled the first schism between East and West in 519 AD, and was signed by the Patriarch of Constantinople:

The first condition of salvation is to keep the norm of the true faith and in no way to deviate from the established doctrine of the Fathers.

For it is impossible that the words of our Lord Jesus Christ, who said, “Thou art Peter, and upon this rock I will build my Church,” [Matthew 16:18], should not be verified. And their truth has been proved by the course of history, for in the Apostolic See the Catholic religion has always been kept unsullied.

…[Condemns heretics]…

Following, as we have said before, the Apostolic See in all things and proclaiming all its decisions, we endorse and approve all the letters which Pope St Leo wrote concerning the Christian religion. And so I hope I may deserve to be associated with you in the one communion which the Apostolic See proclaims, in which the whole, true, and perfect security of the Christian religion resides.

I promise that from now on those who are separated from the communion of the Catholic Church, that is, who are not in agreement with the Apostolic See, will not have their names read during the sacred mysteries. But if I attempt even the least deviation from my profession, I admit that, according to my own declaration, I am an accomplice to those whom I have condemned. I have signed this, my profession, with my own hand, and I have directed it to you, Hormisdas, the holy and venerable pope of Rome. Formula of Hormisdas

Pope St. Agatho, d. January 681 AD

Peter was pronounced blessed by the Lord of all things, was revealed by the Father of heaven, for he received from the Redeemer of all himself, by three commendations, the duty of feeding the spiritual sheep of the Church; under whose protecting shield, this Apostolic Church of his has never turned away from the path of truth in any direction of error, whose authority, as that of the Prince of all the Apostles, the whole Catholic Church, and the Ecumenical Synods have faithfully embraced, and followed in all things; and all the venerable Fathers have embraced its Apostolic doctrine…

This is the living tradition of the Apostles of Christ, which his Church holds everywhere…

For this is the rule of the true faith, which this spiritual mother of your most tranquil empire, the Apostolic Church of Christ, has both in prosperity and in adversity always held and defended with energy; which, it will be proved, by the grace of Almighty God, has never erred from the path of the apostolic tradition, nor has she been depraved by yielding to heretical innovations, but from the beginning she has received the Christian faith from her founders, the princes of the Apostles of Christ, and remains undefiled unto the end…

Consequently, therefore, according to the rule of the holy Catholic and Apostolic Church of Christ, she [Rome] also confesses and preaches that there are in him two natural wills and two natural operations. Epistle of St. Agatho to the Council of Constantinople III

Pope Adrian I, d. 25 December 795

If you persevere in that orthodox Faith in which you have begun…and [exalt] the holy Catholic and Apostolic Roman Church your spiritual mother, and with the other orthodox Emperors venerated it as the head of all Churches, so will your Clemency, that is protected of God, receive the name of another Constantine…

But the more, if following the traditions of the orthodox Faith, you embrace the judgment of the Church of blessed Peter, chief of the Apostles, and, as of old your predecessors the holy Emperors acted, so you, too, venerating it with honour, love with all your heart his Vicar, and if your sacred majesty follow by preference their orthodox Faith, according to our holy Roman Church. May the chief of the Apostles himself, to whom the power was given by our Lord God to bind and remit sins in heaven and earth…

For let sacred authority lay open the marks of his dignity, and how great veneration ought to be shown to his, the highest See, by all the faithful in the world. For the Lord set him who bears the keys of the kingdom of heaven as chief over all, and by Him is he honoured with this privilege, by which the keys of the kingdom of heaven are entrusted to him…

For the blessed Peter himself, the chief of the Apostles, who first sat in the Apostolic See, left the chiefship of his Apostolate, and pastoral care, to his successors, who are to sit in his most holy seat forever. And that power of authority, which he received from the Lord God our Saviour, he too bestowed and delivered by divine command to the Pontiffs, his successors. Epistle of Pope Hadrian to The Council of Nicaea II