Athanasius (c. 296-373) was born in Alexandria. In AD 312, bishop Alexander of Alexandria caught sight of a group of boys imitating church services; one boy, Athanasius, played the part of the bishop and performed mock baptisms, which Alexander found amusing, so he took him into his care, later appointing Athanasius as his secretary and archdeacon. In the year 325, Athanasius accompanied Alexander to the First Ecumenical Council of Nicea, where the young bishop distinguished himself for his ardent opposition to Arianism. On June 8, 326, Athanasius became the bishop of Alexandria. During his 46-year bishopric, he was deposed and banished five times by members of the remaining Arian party. He died in AD 373. In later years, Constantine the Younger would remember Athanasius as "the man of God”; Theodoret, would call him "the great enlightener"; and John of Damascus would hail him as “the corner-stone of the church of God."

According to Athanasius, the “rock” of Matt 16:18 should be identified as Peter’s confession of faith. In one of his festal letters, Athanasius wrote the following:

But ye are blessed, who by faith are in the Church, dwell upon the foundations of the faith, and have full satisfaction, even the highest degree of faith which remains among you unshaken. For it has come down to you from Apostolic tradition, and frequently has accursed envy wished to unsettle it, but has not been able. On the contrary, they have rather been cut off from their attempts to do so. For thus it is written, 'Thou art the Son of the Living God,' Peter confessing it by revelation of the Father, and being told, 'Blessed art thou Simon Barjona, for flesh and blood did not reveal it to thee, but My Father Who is in heaven,' and the rest. No one therefore will ever prevail against your Faith, most beloved brethren.

Here, Athanasius stated that no one will ever be able to prevail against the faith, which he seems to equate with the “rock” of the Church. This is confirmed in one of his homilies on Psalm 11. There he wrote: “In Thy saints, who in every age have been well pleasing to Thee, is truly Thy faith; for Thou hast founded the world on Thy faith, and the gates of hell shall not prevail against it.” Thus, the “rock” for Athanasius appeared to be a believer’s faith in the fact that Jesus is the Christ. Despite the fact that Athanasius had frequent contact with the Bishop of Rome and held the church there in high esteem, it does not appear that he understood this verse to provide the pope with the apostolic office and authority of Peter.

Hilary Pictaviensis (d. AD 368) is believed to have been born to wealthy parents in the town of Poitiers, France. Hilary embraced Christianity in his middle years along with his wife and daughter. Around the year 350, he became bishop of Poitiers and took a strong stance against Arianism, which was devastating the Gallic church at the time. This earned him the honorific “Athanasius of the West.” For his support of orthodoxy, he was banished by Constantine to Phrygia in Asia Minor, where Arianism maintained a strong foothold. Here, between 356 and 361, he wrote the main work of his life, On the Trinity. He died quietly on Jan. 13, 368.

On one hand, Hilary did not seem to have a problem asserting that Peter is the rock of the church. He stated the following in his tractate on Ps. 131:

He [Jesus] took up Peter – to whom He had just before given the keys of the kingdom of heaven, upon whom He was about to build the church, against which the gates of hell should not in any way prevail, who whatsoever he should bind or loose on earth, that should abide bound or loosed in heaven – this same Peter … the first confessor of the Son of God, the foundation of the church, the doorkeeper of the heavenly kingdom, and in his judgment on earth a judge of heaven.

Here, Hilary stated that Peter was the one “upon whom [Christ] was about to build his church.” The apostle is seen to be the first confessor of the Son of God and the keeper of the gate of heaven, so clearly Peter was given special attention and honor. On the other hand, Hilary was equally (if not more so) rigorous in proclaiming that the “rock” in question is Peter’s faith, not the apostle himself. For example, in his treatise On the Trinity, Hilary stated: “This is, therefore, the one immovable foundation, that is, the one blessed rock of faith, which confessed through the mouth of Peter: ‘Thou art the Christ, the Son of the Living God.’” He continued the “rock-faith” parallel in the same treatise, where he later wrote:

It is not the evangelical or apostolic faith to believe that He is the Son of God in name rather than in nature. If this name is one of adoption and therefore is not the Son because He came forth from God, I ask why did the blessed Simon make this confession, ‘Thou are the Christ, the Son of the living God.” Do not all have the power to be born as sons of God through the sacrament of regeneration? … And the Father, by declaring, ‘This is My Son’ revealed to Peter that he should say: ‘Thou art the Son of God. The one who reveals is indicated by the words ‘This is,’ but the knowledge of the one who confesses by the words “Thou art.’ It is upon this rock of the confession that the Church of Christ rests. But the sense of flesh and blood does not reveal the knowledge of the confession …This faith is the foundation of the Church and the gates of hell are powerless against her.

Again, Hilary declared that it was Peter’s faith that is the “rock” of the church. Therefore, the church is maintained and supported not by a single man (Peter), but by the faith that that man expressed in Jesus; that same faith is proclaimed by every true Christian. In other words, the Church of Christ is built on nothing less than the declaration that Jesus is the long-awaited Messiah; he is the Son of God. For Hilary, faith in Jesus, not Peter, is the focal point of the verse. Therefore, it appears that Hilary’s understanding of Matt 16:18 wa not at all concerned with a permanent apostolic see in Rome.

Ambrosiaster is the name was given to the author (c. 366-384) of a set of commentaries on the 13 epistles of Paul; the medieval writers ascribed all but one of these works to St. Ambrose. An incidental remark on 1 Timothy 3:15 shows that the documents were probably written during the pontificate of Damasus (366-384). Erasmus was the first theologian to challenge the authoriship and Ambrose is universally denied as the author of the works.  Many people, including “Hilary the Deacon” and Hilary, a layman and Proconsul of Africa, have been suggested as possible authors. Whoever the author may be, there is little hope that the documents remain in their original form; copyists appear to have inserted many sayings from Augustine, Chrysostom, Jerome, and others into the work. Despite the problems with the writings, the commentaries use of the old Latin version and its reference to various readings, provide great help in the area of textual criticism.  Like Ambrose, Ambrosiaster maintained that the “rock” of Matt 16 is Peter’s faith. In Commentary on Ephesians, Ambrosiaster wrote:

‘Built upon the foundation of the apostles and prophets, Christ Jesus himself being the cornerstone.' The above puts together New and Old Testaments. For the apostles proclaimed what the prophets said would be, although Paul says to the Corinthians: 'God placed the apostles first, the prophets second' (1 Cor. 12.28). But this refers to other prophets, for in 1 Cor Paul writes about ecclesiastical orders; here he is concerned with the foundation of the Church. The prophets prepared, the apostles laid the foundations. Wherefore the Lord says to Peter: 'Upon this rock I shall build my Church,' that is, upon this confession of the catholic faith I shall establish the faithful in life.

According to Ambrosiaster, the prophets prepared the foundation of the Church and the apostles were the foundation of the Church. The “rock” of the Church, though, is the catholic confession of faith in Jesus as the Christ. In other places, Ambrosiaster affirmed the primacy of Paul in a way that would seem to be prejudicial to Peter. In Commentary on Galatians, Ambrosiaster wrote:

By the apostles who were somewhat distinguished among their colleagues, whom also he, Paul, because of their constancy calls 'pillars', and who had always been intimate with the Lord, even beholding his glory on the mount, by them he (Paul) says the gift which he received from God was approved; so that he would be worthy to have primacy in preaching to the Gentiles, even as Peter had the primacy in preaching to the circumcision. And even as he gives colleagues to Peter, outstanding men among the apostles, so he also joins to himself Barnabas, who was associated with him by divine choice; yet he claims the privilege of primacy granted by God for himself alone, even as it was granted to Peter alone among the apostles, in such a way that the apostles of the circumcision stretched out their right hands to the apostles of the Gentiles to manifest a harmony of fellowship, that both parties, knowing that they had received from the Lord a spirit of completeness in the imparting of the gospel, might show that they were in no way appointing one another.

Although the above quotation does not specifically reference Matt 16, it does show that Ambrosiaster did not have a vision of Peter being the sole spokesman of the Church; Paul and Barnabas also wielded a great amount of authority. If Peter can claim to be the foundation of the Church for the Jews, then Paul can claim to be the foundation of the Church for the Gentiles. In any case, Ambrosiaster does not appear to use this verse to affirm the succession of bishops from Peter or the perpetuity of the apostle’s office.

Theodoret (c. AD 393-458) was born at Antioch. After distributing his property to the poor, he entered the monastery of Nicerte in c. 416 and became bishop of Cyrrhus in Syria in 423. He is chiefly known for his involvement in the theological disputes between Cyril of Alexandria and Nestorius. Theodoret was a friend and admirerer of Nestorius, and in a polemical work against Cyril, he explained that the term theotokos should only be applied to Mary in a figurative sense. After the Council of Ephesus, he continued to oppose Cyril and the council’s findings against Nestorianism. He was eventually deposed at the Latrocinian council and forced into exile. When the emperor Marcion ordered Theodoret to attend the Council of Chalcedon in 451, he obeyed and anathematized Nestorius by stating: “Anathema to Nestorius and to everyone who denies that the Holy Virgin Mary is the mother of God, and [to everyone] who divides the one Son, the Only-gotten, into two Sons.” After condemning his friend, Theodoret was restored to his bishopric; he died in AD 458, during the pontificate of Leo I.

Like many of the fathers before him, Theodoret appears to vacillate on the identity of the “rock” of Matt 16. In an epistle to John the Economus, Theodoret stated:

Let us hear the words of the great Peter, 'Thou art the Christ, the Son of the living God.' Let us hear the Lord Christ confirming this confession, for 'On this rock,' He says, 'I will build my church and the gates of Hell shall not prevail against it.' Wherefore too the wise Paul, most excellent master builder of the churches, fixed no other foundation than this. 'I,' he says, 'as a wise master builder have laid the foundation, and another buildeth thereon. But let every man take heed how he buildeth thereon. For other foundation can no man lay than that is laid, which is Jesus Christ.' How then can they think of any other foundation, when they are bidden not to fix a foundation, but to build on that which is laid? The divine writer recognizes Christ as the foundation, and glories in this title.

Here, Theodoret seemed to state that Jesus is the rock and foundation of the Church. Like the other members of this school of interpretation, Theodoret was heavily influenced by Paul’s words in 1 Cor 3. In other writings, though, Theodoret clearly identified Peter’s faith as the pevtra. For example, in Commentary on the Canticle of Canticles, he wrote: “Surely, he is calling pious faith and true confession a rock. For when the Lord asked his disciples who the people said he was, blessed Peter spoke up … and the Lord answered … ‘I say to you, you are Peter and upon this rock I will build my Church.’” Theodoret praised Peter’s faith. In a letter to Eulalius, Theodoret wrote: “Wherefore our Lord Jesus Christ permitted the first of the apostles, whose confession He had fixed as a kind of groundwork and foundation of the Church, to waver to and fro, and to deny Him, and then raised him up again.” Despite the fact that Theodoret called Peter “the first of the disciples,” it is the confession, not the man, which grounds the Church. Thus, it appears that Theodoret did not use Matt 16:18 to lend support to the Petrine authority to the Bishop of Rome.

Cyrillus (d. AD 444) became patriarch of Alexandria about the year 412. He was the nephew of Theophilus, who deposed and banished John Chrysostom. When Theophilus died on Oct. 15, 412, Cyril assumed his bishopric. Almost immediately he closed all the churches of the Novatians in Alexandria, and seized their ecclesiastical property. In the year 415, he used armed force to attack Jewish synagogues who opposed his authority in the city; some Jews were even put to death. From 428 to his death in 444 his life was marked by the frequent Christological controversies. Most notably, he was the chief opponent of Nestorius at the Council of Ephesus in A.D. 431.

Like the aforementioned theologians, Cyril maintained that the “rock” of Matthew 16 remained Peter’s faith. In Commentary on Isaiah, Cyril stated: “When [Peter] wisely and blamelessly confessed his faith to Jesus saying, 'You are Christ, Son of the living God,' Jesus said to divine Peter: 'You are Peter and upon this rock I will build my Church.' Now by the word 'rock', Jesus indicated, I think, the immoveable faith of the disciple.” Thus, Cyril clearly linked of the “rock” in question to the apostle’s faith. This is confirmed in Dialogue on the Trinity, where he wrote: “ ‘And I tell you, you are Peter, and upon this rock I will build my Church, and the gates of hell shall not prevail against it.' The rock, I think, is nothing other than the firm and solid faith of the disciple.” Again, it is Peter’s faith that was linked to the “rock” in question. According to Catholic scholar Michael Winter, it was Cyril’s “preoccupation with Christological questions that influenced his exegesis of Matthew 16.” Even if that is the case, Cyril’s exegesis stands as it is:  the apostle’s confession of faith, not the apostle himself, serves as the rock of the Church. Thus, it appears that Cyril did not use this verse to support the perpetuity of the papal office or the apostolic authority that it wields.