He said to them, “But who do you say that I am?” Simon Peter said in reply, “You
are the Messiah, the Son of the living God.” Jesus said to him in reply, “Blessed are
you, Simon son of Jonah. For flesh and blood has not revealed this to you, but my
heavenly Father. And so I say to you, you are Peter, and upon this rock I will build my
church, and the gates of the netherworld shall not prevail against it. I will give you the
keys to the kingdom of heaven. Whatever you bind on earth shall be bound in heaven; and
whatever you loose on earth shall be loosed in heaven.”
Matthew 16, 16-19

In Roman Catholic theology, papal infallibility is the doctrine that the pope, acting as the supreme leader or shepherd under extraordinary circumstances, cannot err when he teaches matters in faith and morals. This doctrine is based on the belief that Jesus entrusted his Church with a teaching mission whose mandate required that it remain faithful to Christ’s teaching under the guidance of the Holy Spirit, who guarantees that what the Church teaches is always absolutely true and can be accepted with absolute certainty without any shadow of a doubt. The charism of papal infallibility ensures that the Church teaches only Christ's teachings without the slightest taint of adulteration in his teachings. Meanwhile, this doctrine is related to but distinguished from the concept of the Church’s indefectibility, viz., the doctrine that the grace Jesus has promised his Church assures its preservation of the faith until our Lord returns in glory at the end of time.

The definition of the First Vatican Council (1869-70) states the conditions under which the pope has spoken infallibly or ex-cathedra (“from his chair” of supreme teacher): 1. “The Roman pontiff speaks;” 2. “he speaks ex-cathedra;” 3. “defines the following;” 4. “that doctrine concerning faith and morals;” 5. “must be held by the whole Church.” We have one instance of a pope speaking ex-cathedra with infallibility in the Apostolic Constitution, Benedictus Deus, of Pope Benedict Xll in A.D. 1336.

1 (The Roman Pontiff speaks)

“The Apostolic Constitution, Benedictus Deus, of Pope Benedict Xll”

2 (Speaks ex-cathedra)

“with apostolic authority”

3 (We pronounce, declare, and define)

“define the following”

4 (That doctrine concerning faith and morals)

Pope Benedict declares ex-cathedra that each soul will be particularly judged immediately after death

according to his or her deeds before the general day of judgment.

5 (Must be held by the whole church)

“which is to remain in force forever”

According to the First Vatican Council, papal infallibility is a dogma of the Catholic Church. This means that the Pope, as the supreme leader and head shepherd, is protected by the Holy Spirit from making any errors in matters of doctrine. This protection is given when the Pope appeals to his universal primacy of authority, and it is based on Jesus' promise to Peter. This dogma was first given to the apostolic church and has been passed down through the deposit of faith, which includes both Scripture and Tradition.

According to the Catholic Church, the Pope holds two important positions - he is the visible head of the Church and also the head of the episcopal college. When Jesus established the Twelve, he formed them as a permanent assembly, with Peter as their leader. In the same way, the Roman Pontiff (who is Peter's apostolic successor) and the bishops around the world (who are the successors of the rest of the apostles) are united in a bond of unity, forming a single apostolic college. This is explained in the Catechism of the Catholic Church, section 880.

Jesus made Simon, whom he would name Peter, alone the “rock” of his Church. He gave Peter the “keys” of his Church and established him as shepherd of the entire flock. The office of “binding and loosing” was given to Peter and assigned to the College of Apostles, united to its head (CCC, 881). Bishop Vincent Ferrier Gassier explains the importance of this prerogative that our Lord conferred on Peter. “The purpose of this prerogative is preserving truth in the Church. The special exercise of this prerogative occurs when there arise somewhere in the Church scandals against the faith, i.e., dissensions and heresies that the bishops of the individual churches or even gathered together in the provincial council are unable to repress so that they are forced to appeal to the Apostolic See (in Rome) regarding the case, or even the bishops themselves are infected by the sad strain of error” (The Gift of Infallibility: Ignatius Press, 2008). This pastoral office of Peter and the other apostles belongs to the Church’s foundation. It is continued by the bishops united to the Pope under his universal primacy of authority.

The Bishop of Rome, who is the Pope in a universal capacity as Peter’s successor in the divine office, “is the perpetual and visible source and foundation of the unity both of the bishops and of the whole company of the faithful” (CCC, 882). The Roman Pontiff, because of being the Vicar of Christ and as pastor of the entire Church, has “full, supreme, and universal power over the whole Church, a power which he can always exercise unhindered” (CCC, 883). Thus, the College of Bishops has no authority or power to teach with infallibility unless it is united with the Pope since he has succeeded Peter as head of the entire Church, both clergy and laity. As such, the college has “supreme and full authority over the universal Church, but this power cannot be exercised without the agreement of the Roman Pontiff.” The College of Bishops exercises its authority formally and solemnly in an ecumenical council. But “there never is an ecumenical council which is not confirmed or at least recognized as such by Peter’s successor” (CCC, 884). On the occasion of an ecumenical council in which the College of Bishops defines matters of faith and morals in union with the Pope, there is the exercise of what we call the Universal Magisterium.

In order to determine whether the Roman Pontiff has been bestowed with the gift of infallibility as the apostolic successor of Peter, it is essential to turn to the New Testament. We need to examine the meaning of the words "rock" and "keys", as well as the power to "bind and loose". Additionally, it is important to explore the ancient Jewish roots of Peter's unique office, which lends it credibility and establishes its validity.

Scriptural support for the pre-eminence of Peter in the nascent church and his unique role as head shepherd is found in the fact that his name is mentioned no less than 191 times in the New Testament. Next in line is the beloved disciple John, who is mentioned 48 times. However, if this isn’t strong enough evidence, we can turn to the list of the apostles in the Gospel of Matthew to support the Church’s tradition. We read in Chapter 2, Verse 1: “The names of the twelve apostles are these: First, Simon called Peter,” The Greek word for “First” that describes Peter is protos (πρῶτος). Methodist theologian and professor James H. Strong defines the word “before, principal, most important” (Strong’s Exhaustive Concordance of the Bible: Hendrickson, 2009. Entry 4413. Protos).  In other words, among the apostles, Peter is “first and foremost” or “primary first.” Peter’s description as being “first” is not “an arbitrary numerical detail” or a “chronological indicator” of when Peter became an apostle. We see in John 1:41 that Peter’s brother Andrew was the first one Jesus chose to be an apostle of his. Peter’s name appears first in the list of apostles because he is the “primary” apostle within the entire college (John Salza, The Biblical Basis for the Papacy: Our Sunday Visitor Publishing Division, 2007).

Other New Testament writers use protos to describe the pre-eminence of individuals. Luke uses protos to describe Publius as “the chief (protos) man on the island” (Acts 28:7). He was the chief magistrate of the island of Melita and a man of authority. Paul also describes himself as a sinner “of whom I am the chief (protos). Other translations have Paul humbly describe himself as the “foremost” sinner (1 Tim 1:15). In the Septuagint (Old Testament), protos is also used as a title of pre-eminence. The sacred author describes the “chief (protos) singers appointed, to praise with canticles, and give thanks to God” (2 Ezdra 12:45; 2 Neh in the RSV-CE). So, Peter is described as “the first” of the apostles because he is the “chief” or “foremost” among them. He holds a pre-eminent place in the apostolic college (The Biblical Basis for the Papacy).

This fact becomes more evident when we see how Jesus and Peter relate to each other while they are together during our Lord’s three-year public ministry. To begin, Peter is the first apostle to profess the divinity of Christ. Jesus tells him that he has received this divine knowledge by a special revelation from God the Father (Mt 16:16-17). As we have noted, Jesus built his Church only on Peter, the rock, with the other apostles as the foundation and Jesus as the cornerstone or head (Mt 16:18). And the keys which represent authority over the entire Church (clergy and laity) are given only to Peter (Mt 16:19). Further, a tax collector approaches Peter for Jesus’ tax payment because he must be aware that the apostle is our Lord’s spokesperson (Mt 17:24-25). This incident illustrates what Catholics mean about the pope being the vicar of Christ. He speaks for Christ, and our Lord speaks through him when declaring ex-cathedra. In fact, Jesus pays the half-shekel tax with one shekel for himself and Peter (Mt 17:26-27) since he is our Lord’s representative on earth.

We have an example of Peter assuming a leadership role among the apostles when he asks Jesus to explain the rules of forgiveness for all to understand (Mt 18:21). He actually speaks on behalf of all the apostles, besides himself, when he assures Jesus that they have left everything to follow him (Mt 19:27; cf. Mk 10:8). In the Garden of Gethsemane, at the start of our Lord’s passion, Peter and the apostles are sound asleep while Jesus is praying. But our Lord asks no one else but Peter why he was sleeping at this hour. This is because Peter is accountable to Jesus in a unique way above the rest of the apostles. Since he has been appointed as their leader, he should be awake or alert and set a good example to the others (Mk 14:37).

It's intriguing that Jesus chose to preach from Peter's boat (Lk 5:3). In the Bible, a boat is often used as a metaphor to represent the Church. This is the case with Noah's Ark in the Old Testament. This verse suggests that Jesus guides his Church in all truth through his vicar. It's significant that Jesus chose Peter's boat to instruct him to lower his net again for a catch of fish, which turned out to be miraculous (Lk 5:4, 10). Jesus identified Peter as the chief "fisher of men." Without Jesus, he wouldn't have been able to catch such an extraordinary number of fish when they weren't active. Peter's divine office is based on the authority of Jesus the Head, and his exercise of office depends on his grace to be productive.

In the Gospel, Peter is depicted as the spokesperson for the apostles. This is evident when Jesus asks who touched his garment, and Peter is the one who answers on behalf of the rest (Lk 8:45). It seems that none of the other apostles dared to speak up first, as they saw Peter as their leader. At other times, Peter is also the first to speak and acts as the representative of the group. For example, he speaks first during the transfiguration of Jesus, having been the first apostle to reach the mountaintop (Lk 9:28, 33). Additionally, he seeks clarification of a parable on behalf of the other apostles (Lk 12:41).

In Luke 22:31-32, Jesus prays for Peter alone, asking that his faith may remain steadfast. Jesus also charges Peter with the responsibility of supporting the other apostles and ensuring their faith remains strong. This is important because Peter held a position of authority among the apostles, and it was crucial that he remained faithful in order to maintain the unity of the apostolic college. Our Lord's grace is designed to help Peter stay free from teaching error, and that same grace is bestowed on the other apostles, but with Peter's collaboration.

In the Gospel of John, during the Last Supper, Jesus chose to wash Peter's feet as an example of what it means to be a servant of servants (Jn 13:6-9). Although Peter could have washed the feet of the other apostles in emulation of Jesus who "did not come to be served but to serve" (Mt 20:28), it is not recorded that he did so. Jesus then asked Peter in front of the other apostles if he loved him more than they did (Jn 21:15). This was because Peter had been appointed the visible head of the apostolic see and his allegiance was primarily to Christ without any compromise. Shortly before leaving to return to the Father, Jesus told Peter to "feed [his] lambs" and "feed [his] sheep" (Jn 21:15-17). These "lambs" or "sheep" refer to all people, including the apostles. As the first pope, Peter was charged with the primary responsibility of tending to the faith of the clergy and the laity in a universal capacity.

In Matthew 16:13-19, Peter's unique role as the first of the apostles is clearly defined. He possessed the supernatural ability to intuit divine knowledge from God, which is a fundamental Christological truth, and communicate it without error to the apostles who were present. The Catholic Church believes in the concept of papal infallibility, which means that the pope isn't infallible by nature, but rather, by the operation of the Holy Spirit who guides his thoughts. When Simon pronounced the first papal infallible decree in Church history, Jesus changed his name to Peter, which means "rock" in Greek (Petros). The name "Cephas," also spelled Kepha, is a Greek transliteration of the Aramaic word for rock, and is mentioned in Jn 1:42, 1 Cor 1:12, 3:22, 9:5, 15:5, and Gal 2:9.

The Greek text is a translation of Jesus’ words, which were actually spoken in Aramaic. Aramaic only had one word for rock, kepha which explains why Peter is often called Cephas in the Bible. The word kepha in Aramaic means “huge rock.” The Aramaic word for “little stone” is evna and Peter isn’t called “Evna.” In Aramaic, Jesus said “You are Peter (Kepha) and upon this rock (kepha) I will build my Church.” The metaphor works well in Aramaic where nouns are neither feminine nor masculine.

D. A. Carson explains, “… the words petros and petra were synonyms in first-century Greek. They meant “small stone” and “large rock” in some ancient Greek poetry, centuries before the time of Christ, but that distinction had disappeared from the language by the time Matthew’s Gospel was rendered in Greek. The difference in meaning can only be found in Attic Greek, but the New Testament was written in Koine Greek—an entirely different dialect. In Koine Greek, both petros and petra simply meant “rock.” If Jesus had wanted to call Simon a small stone, the Greek lithos would have been used” ( The Expositor’s Bible Commentary [Grand Rapids: Zondervan, 1984], Frank E. Gaebelein, ed., 8:368).

In the Kingdom of David, the king who ascended to the throne would appoint a chief steward to rule and govern in his absence. The king would formally grant his chief steward with this authority by presenting him with the keys to the kingdom. The chief steward, also known as the vizier or vice-regent, was said to be "over the house" of the king, which was the house of David. He would be second only to the king and have full power over the palace and the authority to pass judgment over the king's subjects. Jesus came into the world to restore the kingdom of David in a new dimension. He presented his chief steward, or vicar, with the keys to a visible kingdom, which is the Church on earth. He appointed Peter to rule over "the house of God" (2 Cor 5:1; 1 Tim 3:15; 1 Pet 4:15), who would govern God's household in the king's absence after his ascension into heaven.

The Hebrew Scriptures mention “keys” only once, in the context of the authority of the Davidic king’s chief steward. Around 715 B.C., Hezekiah was the king of the Southern Kingdom, and Shebna was his chief steward or vice-regent. Through the prophet Isaiah, God reveals that He will remove Shebna from his office and replace him with Eliakim, to whom he will give the “key to the house of David.”

This is what the Lord, the Lord Almighty, says:
Go, say to this steward,
to Shebna the palace administrator:
What are you doing here and who gave you permission
to cut out a grave for yourself here,
hewing your grave on the height
and chiseling your resting place in the rock?
“Beware, the Lord is about to take firm hold of you
and hurl you away, you mighty man.
He will roll you up tightly like a ball
and throw you into a large country.
There you will die
and there the chariots you were so proud of
will become a disgrace to your master’s house.
I will depose you from your office,

“In that day I will summon my servant, Eliakim son of Hilkiah. I will clothe him with your robe
and fasten your sash around him and hand your authority over to him. He will be a father to
those who live in Jerusalem and to the people of Judah. I will place on his shoulder the key to the
house of David; what he opens no one can shut, and what he shuts no one can open. I will drive
him like a peg into a firm place; he will become a seat of honor for the house of his father.
Isaiah 22, 15-23

In this passage, Eliakim is given the key to the house of David, which was previously held by Shebna. This position is transferable by appointing successors. As the holder of the key to David’s kingdom, whatever Eliakim opens cannot be shut by anyone and whatever he shuts cannot be opened by anyone. This means that his final judgment is indisputable and irrevocable, as he represents the king in his absence and speaks on his behalf. Eliakim will be known as a “father” to Israel while exercising his office. Just as God was directly involved in the administration of his kingdom in the Old Testament, He is in charge of the administration of His kingdom in the New Testament.

It is significant that God revealed the succession of the chief steward during the reign of King Hezekiah. This is evidenced in Isaiah 7:14.

Therefore, the Lord Himself will give you a sign:
Behold, the virgin shall conceive and bear a Son,
and shall call His name Immanuel.
Isaiah 7, 14

In the book of Revelation, John sees a "great sign" in heaven, which symbolizes the restoration of the Davidic Messianic kingdom through the birth of the Messiah King by the Blessed Virgin Mary (Rev 12:1-5). This event fulfills all the Old Testament prophecies of the restoration (cf. Micah 5:1-3). Among the Davidic kings, Hezekiah is considered to be the one who prefigures the Messiah most closely. From a Christian perspective, Hezekiah is seen as resembling Christ more than any other king. In the biblical account, God decrees Hezekiah's sickness unto death and then promises to raise him up or heal him on the third day.

In those days Hezekiah became ill and was at the point of death. The prophet Isaiah son of Amoz
went to him and said, “This is what the Lord says: Put your house in order, because you are going
to die; you will not recover.” Hezekiah turned his face to the wall and prayed to the Lord,
“Remember, Lord, how I have walked before you faithfully and with wholehearted devotion and
have done what is good in your eyes.” And Hezekiah wept bitterly. Before Isaiah had left the
middle court, the word of the Lord came to him: “Go back and tell Hezekiah, the ruler of my
people, ‘This is what the Lord, the God of your father David, says: I have heard your prayer and
seen your tears; I will heal you. On the third day from now you will go up to the temple of the Lord.
2 Kings 20, 1-5

On the third day, God raised Hezekiah, making him the most important Messianic figure among the kings who inherited David's throne. As the king symbolizes the Messiah, his kingdom symbolizes the kingdom of our Lord and King in the house of David. Just like Hezekiah had a series of chief stewards, Jesus also had a succession of chief stewards. Linus became the first successor to Peter in A.D. 67 (see 2 Tim 4:21; Irenaeus, Against Heresies 3, 3:3 [189 AD]). Eliakim was known as a "father" to Israel in the kingdom of Judah, so Peter and his successors were known as "holy fathers" in the new kingdom or house of Israel, which is the Church. Thus, we have a biblical precedent for appointing Peter as the steward or vicar of Jesus' kingdom on earth. Now, let us move on to the topic of binding and loosing.

As we have seen, just as Eliakim had the authority to “open and shut,” Peter is also given the authority to “bind and loose.” Since this authority is derived from possessing the keys to the kingdom, Jesus confers this authority on Peter alone and not also on the Twelve. John Salza explains what the terms binding and loosing mean in a Jewish context. “’Binding and loosing’ (Heb. asar ve-hittar) were standard rabbinical terms used by the Jewish religious authorities of the day. These terms described their legislative and judicial authority to ‘forbid’ or ‘permit.’ This included rules of conduct (halakah) for God’s people and issuing definitive interpretations of Scripture, oral tradition, and the whole of the Mosaic law. In short, the terms described the Pharisees’ authority over doctrinal and disciplinary matters” (The Biblical Basis for the Papacy).

In Acts 15:12-17, Peter exercised his authority during a general council in Jerusalem. The council discussed the doctrinal and disciplinary issue of whether Gentiles should be circumcised after baptism. None of the apostles disputed Peter's statement as Christ's chief steward on earth. Only after Peter spoke did Paul and Barnabas (who were bishops) offer their support. James, the Bishop of Jerusalem, presided over the council and also agreed with Peter's declaration.

During the time of Jesus, the scribes and Pharisees were the religious teachers of Israel and the successors of Moses. In Matthew 23:2-4, Jesus refers to the "chair of Moses," which represented their authority to interpret and explain the Mosaic law. The chair was typically located in the middle of a synagogue, where the official teacher of the Law would sit to read the Scriptures and address the congregation. This tradition is based on Exodus 18, where God says, "And the next day, Moses sat to judge the people" (v. 13). Moses made judgments based on God's will while sitting in the chair. In verses 15-16, Moses explains that the people come to him to seek God's judgment, and he judges between them and teaches them God's laws. This tradition of authority and the chair were passed down through generations to Joshua, the judges or elders, the prophets, and finally to the Sanhedrin of Jesus' time (The Biblical Basis for the Papacy). The chair represented the divine office, which required successors to carry on the tradition.

Jesus recognized the scribes and Pharisees as valid heirs to the teachings of Moses and taught with his authority, despite their personal flaws and imperfections. Our Lord instructed the apostles to follow "everything" (panta hosa) they said while sitting on the chair (Mt 23:5-7). Even though Jesus strongly criticized them for misusing their divine authority and exercising it with arrogance and contempt towards the common people, particularly those who were marginalized (Mt 23:5-7, 13), he acknowledged their power to "bind" and "loose," and to "open" or "close" in the kingdom of God concerning matters of faith and morality in accordance with the Torah.

Jesus used terms that were familiar to the Jews when he spoke to Peter, thereby inaugurating a new ruling and teaching authority within the Church. The authority of the teachers of the Law was to be transferred to the teachers of the Law of Christ (Gal 6:2). The New Covenant of grace and charity (agape) was to replace the Law of the Old Covenant, with all its civil and ceremonial prescriptions under the curse of the law. As a result, Peter's chair would replace Moses's chair. Like Moses, Peter would have the authority to "render the judgment of God" (Ex 18:15) and would be the official interpreter of God's word (See 2 Peter 3:16). Peter would have the power Eliakim had to "open" what none could "shut" (Isa 22:22). And with the authority of the Sanhedrin of his time, Peter would be able to "shut the kingdom of heaven against men who separate themselves from his teaching (Mt 23:13). Only Peter and his successors in the papacy have the plenary authority to excommunicate heretics and schismatics from the Church, whether they be clergy or laity.

Hence, there is biblical and ancient traditional support for papal infallibility and the universal primacy of papal authority in the Church that Christ has established. What Peter binds on earth, heaven binds. What Peter looses on earth, heaven looses. Heaven’s reciprocal binding (estai dedemenon) and loosing (estai lelumenon) are in the passive voice. This could be translated as “shall be bound” or “shall having been bound” (The Biblical Basis for the Papacy). Heaven is the place from where Peter receives the power to make important decisions regarding the teachings of the church. These decisions are guided and confirmed by the Holy Spirit, who ensures that Peter's decisions align with divine revelation. Like God revealed to Peter a fundamental truth about salvation through Christ, all of Peter's future official teachings on salvation and those of his successors on the chair will be confirmed by God.

The future tense (“shall be bound”) indicates that heaven’s ratification of Peter’s decisions will have occurred when he made them. Heaven will ratify what Heaven has guided him to say through the Holy Spirit and not by any private judgment of his (flesh and blood) that would amount to an arbitrary theological opinion. “The Holy Spirit’s unique use of the future tense with the passive voice to describe heaven’s reciprocal binding and loosing underscores Peter truly speaks for heaven just as he did when he confessed the divinity of Christ. Peter’s binding and loosing decisions are ordained by God” (The Biblical Basis for the Papacy).

Hence, the concept of papal infallibility implies that God protects Peter and all his successors, who speak ex cathedra, from teaching errors related to faith and morals. The Holy Spirit ensures that their teachings are part of God's revelation. As Jesus promised that his Church would withstand the gates of hell and that the Holy Spirit would guide it towards all truth until his return, the teachings of the Pope from the chair of Peter would always be free from errors. Whenever the Pope makes an ex cathedra pronouncement, it is a definitive teaching related to faith or morals. It is intended to be infallible and accepted by the entire Church without question, thanks to the seal of the Holy Spirit.

Early Sacred Tradition

“The church of God which sojourns at Rome to the church of God which sojourns at Corinth
But if any disobey the words spoken by him through us, let them know that they will involve
themselves in transgression and in no small danger.”
St. (Pope) Clement of Rome
1st Epistle to the Corinthians, 1,59:1
(c. A.D. 96)

“And he says to him again after the resurrection, ‘Feed my sheep.’ It is on him that he builds the
Church, and to him that he entrusts the sheep to feed. And although he assigns a like power to all
the apostles, yet he founded a single Chair, thus establishing by his own authority the source and
hallmark of the (Church’s) oneness. No doubt the others were all that Peter was, but a primacy is
given to Peter, and it is (thus) made clear that there is but one flock which is to be fed by all the
apostles in common accord. If a man does not hold fast to this oneness of Peter, does he imagine
that he still holds the faith? If he deserts the Chair of Peter upon whom the Church was built, has
he still confidence that he is in the Church? This unity firmly should we hold and maintain,
especially we bishops, presiding in the Church, in order that we may approve the episcopate itself
to be the one and undivided.”
St. Cyprian of Carthage
The Unity of the Church, 4-5
(A.D. 251-256)

”The reason for your absence was both honorable and imperative, that the schismatic wolves might
not rob and plunder by stealth nor the heretical dogs bark madly in the rapid fury nor the very
serpent, the devil, discharge his blasphemous venom. So it seems to us right and altogether fitting
that priests of the Lord from each and every province should report to their head, that is, to the
See of Peter, the Apostle.”
Council of Sardica, To Pope Julius
(A.D. 342)

“You cannot deny that you know that in the city of Rome the Chair was first conferred on Peter,
in which the prince of all the Apostles, Peter, sat…in which Chair unity should be preserved by all,
so that he should now be a schismatic and a sinner who should set up another Chair against that unique one.”
St. Optatus of Mileve
The Schism of Donatists, 2:2-3
(c. A.D. 367)

“Philip, presbyter and legate of the Apostolic See, 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 Saviour and Redeemer of the human race, and that to him was given the power of
loosing and binding sins: Our holy and most blessed Pope Celestine the bishop is according to due
order his successor and holds his place…Accordingly the decision of all churches is firm, for the
priests of the eastern and western churches are present…Wherefore Nestorius knows that he is
alienated from the communion of the priests of the Catholic Church.”
Council of Ephesus, Session III (A.D. 431)

“Wherefore the most holy and blessed Leo, archbishop of the great and elder Rome, through us,
and through this present most holy synod together with the thrice blessed and all-glorious Peter
the Apostle, who is the rock and foundation of the Catholic Church, and the foundation of the
orthodox faith, hath stripped him of the episcopate, and hath alienated from him all hieratic
worthiness. Therefore let this most holy and great synod sentence the before mentioned Dioscorus
to the canonical penalties.”
Council of Chalcedon, Session III (A.D. 451)

But I have prayed for thee, that thy faith fail not:
and thou, being once converted, confirm thy brethren.
Luke 22, 32