Matthew 16:18 myths


Something which keeps coming up, and being misunderstood, is the interesting interplay of πετρα and πετρος in Mt 16:18. Now, I am not a Catholic, but I would nonetheless say that that verse does support Petrine primacy, and I would like to explain how.

In Greek, Mt 16:18 reads καγω δε σοι λεγω (“and I-myself say to you”) οτι συ ει πετρος (“that you are Petros”) και επι ταυτη τη πετρα (“and upon this Petra”) οικοδομησω μου την εκκλησιαν (“I will build my church”) και πυλαι 'αδου ου κατισχυσουσιν αυτης (“and the gates of Hades will not stand against her”).

What some anti-Catholics claim is that πετρος and πετρα are wholly-dissimilar, and that Jesus is not saying that he will build his church on Peter; what some Catholics claim is that πετρος and πετρα are utterly identical, and that Jesus is saying that he will build his church only on Peter. Neither of these readings does justice to the text.

The myth of dissimilarity: “You are Rock, but upon this other Stone”
The two terms πετρα and πετρος are closely related. Greek had more than half a dozen other terms for stone (λιθος being the one most often used in the Bible), but the Gospel writer used a pair which share an obvious linguistic root in πετρ- rather than for the distinct difference which would have been achieved by using such terms as “πετρος … λιθωι”.

The “pebble” myth
One of the more common claims of anti-Catholic readings is that πετρα is a mass of stone, while πετρος is a small pebble. Although that description of πετρα is not a bad one, the description of πετρος just does not match the usage in Greek. Homer uses πετρος in Iliad 20.288 for a boulder too large for two mortals to lift; it is subsequently used for boundary stones, and for the stones dropped to kill besiegers ( 7.142Jewish Antiquities). Those are no pebbles. The consistent factor in the usage of πετρος is individuality: it refers to a distinct, separate chunk of stone.

The myth of identity: “You are Rock, and upon you”
The two terms πετρα and πετρος are not identical. The Gospel writer could have used the same term twice (πετρος … πετρωι), or a simple personal pronoun the second time (πετρος … σοι), but did not. This point can be confusing for people whose first language is English, and who thus think that the “natural sense” is that the two are the same because an English translation says “Rock … rock” (but see also Jesus’ “brothers”).

The neologism myth
Πετρος did exist as a common noun before the Gospel, and even, as seen in Josephus, after the Gospel. The claim that it was a neologism might have come from Petrus, the Latin form used in the first part of Mt 16:18, which does not seem to have predated the Latin translation of the Gospel.

The gender myth
Πετρος is not just the masculine form of πετρα, and Jesus did not “have to” use something other than πετρα because he was talking to Simon, a man. First, Greek gender was primarily grammatical, and so Greek could identify usually-masculine people with feminine nouns if one so wished, thus calling Simon “Petra” just like Jesus is “Sophia” (1 Co 1:24, 30). Second, Greek could also switch the grammatical genders of nouns, and we have examples of that with πετρος itself being feminine in Anthologia Palatina 7.274, 479.

“It does not matter, because it was not originally Greek”
The claim that Matthew’s Gospel was originally in “the Hebrew dialect”, and so all of this Greek does not matter, is rather complex. It is based upon Irenaeus’ Adversus Haereses 3.1.1 and Eusebius’ later Historia Ecclesiastica 3.39, both referring back to Papias’ lost work. There is doubt amongst scholars as to whether this does indicate the existence of a Hebrew original to Matthew, or whether Papias was referring to Matthew’s having compiled something like the uncanonized Gospel of the Hebrews. Even if Papias was referring to a Hebrew or Aramaic original for Matthew’s Gospel, we just do not have that text, which makes it very difficult to claim that it “obviously” said, “You are Kephas; upon this Kephas”, especially when Biblical Hebrew, which was closely related to Aramaic, had about ten different words for “rock”, and so another interplay could easily have taken place there. (Also, anyone who believes strongly in the canon is unlikely to be persuaded by an appeal to a text other than the canonized Greek.)

The resulting interplay: “You are Rock, and upon such Rockness”
In Greek, then, we have in Mt 16:18 πετρα, the undifferentiated mass, and πετρος, the distinct chunk of that mass. The different-yet-similar interplay places the two terms in a relationship with one another, and so, (as you can see if you look on p.1079 of Lampe’s Patristic Greek Lexicon,) the early, Greek-reading Church Fathers read it in a variety of interconnected ways, all of which centre around “Simon, you are a-shining-example-of-X and upon X will I build my Church”. Peter is thus identified as the first and foremost of what was to come, and denying his significance there would be as unfaithful to the text as would claiming that he is the only foundation stone in view. The text presents Peter (including his faith and his profession of that faith) as the archetype of Christianity, which makes it an excellent argument for Petrine primacy, if not quite for Petrine supremacy.


Gender might not have been important to others, but it was important to the Jews.

Matthew 16:18 uses the two words that are based on the same word, the only difference being the suffix which was gender sensitive.
πετρος (“Petros”)
πετρα (“Petra”)
Therefore, it is reasonable to assume that Jesus was also basing his two usages of “rock” on the same Aramaic word, “kepha.”

We don’t need the Church Fathers to tell us the original was in Hebrew or Aramaic. The Gospel of John tells us.

**John 1:42
“Then he brought him to Jesus. Jesus looked at him and said, ‘You are Simon the son of John; you will be called Kephas’ (which is translated Petros).”

The whole context of the passage confirms the supremacy of Peter.
**Consider the five things that Jesus declares to Peter in Matthew 16 verses 17 through 19. **
**1. “Blessed are you, Simon son of Jonah.” **

 **2.        “For flesh and blood has not revealed this to you, but my heavenly Father.”**
3.   “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.”**
4.   “I will give      you the keys to the kingdom of heaven.”  **
 **5.        “Whatever you bind on earth shall be bound in heaven; and whatever you loose      on earth shall be loosed in heaven.” **
 **Declarations 1, 2, 4, and 5 are unquestionably favorable to      Peter.  If declaration number 3 was unfavorable to him it would be totally      inconsistent if not contradictory and it would make the whole dialogue      confusing if not incomprehensible.  **

[LEFT]Therefore, both the original language of Aramaic where only one word for rock is used and the context itself shows that Simon is now the Rock on which Christ builds His Church.




Peter’s Supremacy is indicated in other Biblical passages as well.

Saint Peter
Luke 22:29-32 ****
“ ‘… and I assign to you, as my Father assigned to me, a kingdom, that you may eat and drink at my table in my kingdom, and sit on thrones judging the twelve tribes of Israel. Simon, Simon, behold, Satan demanded to have you (plural in Greek), that he might sift you (plural in Greek) like wheat, but I have prayed for you (singular in Greek) that your (singular in Greek) faith may not fail; and when you (singular in Greek) have turned again, strengthen your (singular in Greek) brethren.’ ” RSV (emphasis added in parenthesis to clarify the Greek text.)

**The King James version retains the meaning of the original Greek where Satan had demanded to have “you -plural,” - meaning all of the disciples - but Christ says that He prayed for “you -singular” meaning Peter uniquely.
**Luke 22:31-32 ****
“And the Lord said, Simon, Simon, behold, Satan hath desired to have you, that he may sift you as wheat: But I have prayed for thee, that thy faith fail not: and when thou art converted, strengthen thy brethren.” KJV **
**Christ only started one Church. And He built that Church on Saint Peter. Peter, who as only a man is weak is now made strong by the power of the Holy Spirit. And he is entrusted with special and unique guidance to lead the Church and strengthen the other Apostles. The passage below shows that it was God the Father who singled him out for this special role.
Matthew 16:15-19 ****
“ And I tell you, you are Peter … I will give you ( in the Greek it is “you - singular”) the keys of the kingdom of heaven, and whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven.’ ”RSV (emphasis added in parenthesis to clarify the Greek text.)

**To find the context of the meaning of the keys we look to the Bible, Isaiah 22. **
**Isaiah 22:15, 19-24 ****
“Thus says the Lord, the GOD of hosts: Up, go to that official, Shebna, master of the palace… 19 I will thrust you from your office and pull you down from your station. On that day I will summon my servant Eliakim, son of Hilkiah; I will clothe him with your robe, and gird him with your sash, and give over to him your authority. He shall be a father to the inhabitants of Jerusalem, and to the house of Judah. I will place the key of the House of David on his shoulder; when he opens, no one shall shut, when he shuts, no one shall open. I will fix him like a peg in a sure spot, to be a place of honor for his family; On him shall hang all the glory of his family: descendants and offspring, all the little dishes, from bowls to jugs.” NAB **

**Isaiah 36:1-3 ****
“In the fourteenth year of King Hezekiah, … 3 there came out to him the master of the palace, Eliakim, son of Hilkiah, and Shebna the scribe, and the herald Joah, son of Asaph.” NAB

**The keys represent absolute power to rule. They are owned by the King of Israel who entrusts them to his representative the “master of the palace.” Christ is the true King of Israel who gives his keys to Peter.
**The key of the “house of David” implies succession because King David had been dead for hundreds of years at the time of King Hezekiah’s rule. Just as the king had a successor so did the head of the household, or the “master of the palace.” Or in today’s language we might use the terms “prime minister” or even better “the king’s regent,” “viceroy,” or “vicar” since he had absolute authority under the king. His office was one of being a father to the people, Cf Isaiah 22: 21.

** **John 21:15 ****
“Jesus said to Simon Peter, ‘Simon, son of John, do you love me more than these ?’ He said to him, ‘Yes, Lord, you know that I love you.’ He said to him, ‘Feed my lambs.’” NAB
**Jesus gave over to Saint Peter the care of all of His sheep.
Now the only question is how many Christian sheep belong to Jesus ?
……………Answer: All of them.



Interesting. I’ll have to keep this in mind for my non-Catholic friends. The anti-Catholic interpretation I’ve heard most is that with the second “rock,” Jesus was referring to Himself as the rock upon which he would build His Church. I find that to be one of the silliest and most convoluted arguments someone can make, both logically and grammatically, but it’s still one I’ve heard quite often, and somehow with a straight face every time.


I believe Archbishop Sheen said something similar in his talk on Petrine Primacy.

Excellent analysis. So, basically, both Protestants and Catholics are right. The Church is built on Christ, yes, but the Church is built on Peter who is the cornerstone of the foundation, which is Christ. Our Church is built out of people.


Thank you. You’ve made an argument, considered other arguments, and addressed evidence for and against those arguments, and summed up with why your feel your understanding is the strongest interpretation.

You didn’t yell louder, fill your reply with bold/colour/size bombs or build your argument so that it rests on the premise that the argument is supposed to defend. You work with the text and provide an interpretation that can be harmonized with most (if not all) of the ECF citations on the passage. You cite relevant grammatical evidence and reference works so others can review your claims and use the references to support their own point of view.

While I don’t accept your conclusion 100% at this point, you’ve argued it well enough that it is certainly worthy of consideration and study. I can only hope that others who seek to disprove your argument hold themselves to as high a level of discourse, something not always seen in these forums when discussing this passage.

I look forward to reading a well-documented and well-reasoned catholic or orthodox response to your “myth of identity” as well as any quality response from a protestant who wishes to argue one of the other interpretations you argue against. If you haven’t already done so, you might find “Peter” by Oscar Cullman an enjoyable read. Thank you again. :slight_smile:


Dear Non Serviam,

Is it possible your were referring to my post ???

It was getting late last night. All I had time to do was copy and paste from my web page below on Apostolic Succession, something Anglicans do not have, so I just took the appropriate text. I made that page sometime ago, when i was even less experienced than i am now in knowing how to design them. I was experimenting with color. The effect was not exactly what I wanted. Someday, when i have time i will adjust it.

I was not yelling

If you mistakenly think my arguments rest upon themselves in a circular manner i do not agree.

Peter the Rock and Caesarea Philippi



Thanks for the recommendation.


We can be very good at making ourselves believe things.


It seems to be very much that: Peter is the first foundation.


Thanks for that: I have just found it here, especially from about the 48th minute.


In reality, Fr Stanley L Jaki, S.J. points out that the consummate skill of Jesus in quoting the Bible was manifest in the name He gave to Simon. “Instead of calling Simon sur, he called him Kepha. The former was the chief biblical word for rock, the latter was the Aramaic version, commonly used in Jesus’ time, for the biblical keph, which occurs only a few times in the Old Testament.

“Jesus’ choice of *kepha *left Simon what he was, a mere man, while the very same name grafted on him, through its being closely synonymous with sur, something superhuman.

Fr Jaki concludes that “Christ’s words ‘you are rock,’ have their validity even if Yahweh had never been called Rock in the Old Testament.”[See *And On This Rock, Fr Stanley L Jaki, O.S.B., Trinity Communications, 1987, p 74-81].

Answer by Fr. John Echert (EWTN) on 07-19-2003:
“The original Aramaic name given to Simon by our Lord was “Cepha” which means rock. The Greek equivalent is “Petra” but since this is a feminine noun in Greek, it is rendered with the masculine ending as “Petros” in the New Testament. Contrary to what some non-Catholics claim, the use of “Petros” does not manifest an intention to regard Peter as a small stone rather than a rock but is simply done in accord with the rules of grammar and convention in the Greek. Such is obvious when we consider that the actual name given him by the Lord, “Cepha,” admits of NO such distinction between a small stone and large rock. To the best of my knowledge and based upon the work of other scholars I have read, I am not aware of another instance of this name in antiquity–certainly it was not commonly known or used. So our Lord was not only creating a new position within the New Covenant people but He appears to have done so with a new name.

“I highly recommend the book *Pope Fiction *by a convert to Catholicism, Steve Madrid, which addresses every imaginable attempt to discredit the papacy.”


Actually, I wasn’t. I apologize that I gave you the impression that I was. Since you were polite, and not yelling or posting huge text, I didn’t think you would take it to mean your post. I was referring to the results I’ve read on so many other threads about this topic.

Again, I’m sorry that I gave you the impression I was referring to you. I looked at your pages and found this section of your second page particularly interesting.

While the rock that Caesarea Philippi was built on is an impressive sight, Peter, by Christ’s decree becomes even a greater Rock because the ROCK-ness of Jesus Christ works through him making him a Rock. And upon him Jesus builds His Church to honor the One True God.

In essence, this is almost the same interpretation as the one given in the original post, that the verse refers to Peter and the “rocklikeness” he demonstrated with his confession. I can’t speak for the original poster, but I don’t think he intended this interpretation to cast Peter in a negative light, but rather to make an argument about how the verse could be describing Peter and still be grammatically sound.

Think about this: If I was speaking to you and said “Thou art JohnR77 and upon this JohnR77…” wouldn’t it sound a bit odd to you instead of saying "Thou art JohnR77 and upon you … " or “Thou art JohnR77 and upon you, JohnR77, …”

Why the switch from second person (Thou) to 3rd person (this Rock) when everything else in Jesus words in the passage is spoken in the 2nd person?

Either you end up saying the Greek is a mistranslation of Jesus’ original Aramaic words (and that causes a whole pandora’s box of issues I don’t want to think about) or there needs to be some reason for the switch from 2nd to 3rd person, hence the argument put forward in the original post about Peter and his “rockiness”, the 3rd person reference making sense because it refers to a characteristic of Peter, that describes Peter, but will describe others as well when they develop rocklike faith in Jesus.

Finally to be clear, I don’t find your individual argument to be circular, but rather the argument put forward by Karl Keating, and advocated by many on the forum, to be circular, in spite of the repeated attempts to claim it is “spiral”.

[quote=Trent Horn]The argument for the authority of the Catholic Church is not a circular argument that relies on the conclusion it is trying to establish as one of the premises of the argument. Instead, it is as Karl Keating describes in his book Catholicism and Fundamentalism a spiral argument where the different elements are related but not identical.

In his book Keating says that the authority of the Church does not come from the Bible because the Bible is the inspired Word of God. Instead, if we examine the Bible as an ordinary set of historical documents written in ancient Greek we find that there is good evidence that Jesus of Nazareth rose from the dead and established one Church upon the Apostles, with Peter as the head of the Church.

This authority gives us confidence that the texts gathered into the Biblical canon are inspired. So the argument is not circular. We believe in the Church because we believe in the Bible as a set of reliable, though man-made, historical documents. But then, as Augustine says, we are moved to believe in the inspiration of these biblical books, or their divine authorship, by the authority of the Catholic Church.

The argument does some sleight of hand switching the catholic interpretation of scripture for the text of scripture itself and then claiming that the interpretation provides evidence for the catholic authority to interpret scripture, making it circular.

I hope this clears up any misunderstandings we have. :slight_smile:


I think this argument rests not on whether there was a Hebrew version of Matthew first, but on the fact that Jesus, when He said these words, was speaking in Aramaic. We know this because several times when quoted, the words are Aramaic. Also, we see his name as “Cephas” several times in other books/letters in the NT.

The point is that “Petros” was the translation of what was originally said.


Further, as Sir Arnold Lunn put it in a 1932 letter to C.E.M. Joad:
‘The Catholic claims to prove by pure reason that Christ was God, that Christ founded an infallible Church, and that the Roman Catholic Church is the church in question. Having traveled thus far by reason unaided by authority it is not irrational to trust the authority, whose credentials have been proved by reason, to interpret difficult passages in the Bible.’

It certainly is not circular.


Quite, and we can reasonably infer that the Aramaic used for πετρος was most probably Kephas. What we cannot do is ascertain the Aramaic used for the rest of the passage, since we just do not have it.

Aramaic was closely related to Hebrew, and my concordance says that Hebrew had כּף (keph, related to Aramaic kephas), used for the sort of place in which someone might seek refuge, as well as חלּמישׁ (challamish - flint/rock), טוּר (tur - rock/hill/mountain), מעוז (ma’oz - rock/fortress, in four variants), סלע (sela - rock/fortress), צוּר (tsur - rock/refuge, in four variants). Thus, a Hebrew version of Mt 16:18 could use keph…tur, keph…ma’oz, keph…sela, or keph…tsur to achieve a similar interplay to the πετρος…πετρα interplay in Greek.


Great website. I’ve bookmarked it. I’m going to the Holy Land in November and am looking forward to going to Caesarea Philippi, among all the other places Jesus walked.


Now let’s examine the actual Greek words, Petros and Petra. First of all, by the first century during which time Matthew’s gospel was written, the words Petros and Petra were interchangeable. Petra doesn’t always refer exclusively to a large rock. Just look at 1 Peter 2:8:
A stone(lithos) that will make people stumble, and a rock(petra) that will make people fall.

Here “petra” is understood by the context to mean a small stone which will make people trip, not a huge massive rock. Also, if Jesus really wanted to be clear about Simon Peter being a pebble, the Greek language has a distinct word for this as can be seen in the beginning of verse 8. (lithos = small stone).

Why isn’t Petra used for Peter’s name? First we must realize that Christ did not speak to his disciples in Greek. The common tongue of the time and the language Christ spoke was Aramaic. There is only one word for “rock” in Aramaic and that word is “kepha”. How did we get “Petra” from “kepha”? When Jesus first met Simon, He looked at him and changed his name to Cephas (English transliteration of Greek Kephas which is from the Aramaic word Kepha). This can be seen in John 1:42:
He brought him to Jesus. Jesus looked at him, and said, “So you are Simon the son of John? You shall be called Cephas**Kephas]” (which means Peter{Petros})

If Jesus had wished to give Simon a name to signify a small stone, there were several words in Aramaic which he could have used…“evna” for example.

On St Peter, scholarly commentary identifies that Cephas is merely the transliteration of the Aramaic ‘Kepha’ into Greek. Catholicism And Fundamentalism, Karl Keating, 1988, Ignatius, p 207].

“Transliteration” means to represent words in the characters of another alphabet. Convert David B Currie puts it this way: “Kepha] transliterated into English, can be written ‘Cephas’.” Born Fundamentalist, Born Again Catholic, 1996, Ignatius, p 76]. Since “Kepha” is the only Aramaic word for rock, Currie points out that Jesus said: “I tell you that you are Rock (Kepha) and on this Rock (Kepha) I will build my Church.”

“Sur” was the chief biblical word for rock, and the Psalms emphasised that God was the only Rock (sur). “Being closely synonymous with “sur”, the name *Kepha *could not help but evoke in pious Jews, as all the twelve were, a sentiment of awe and reverence.” And On This Rock, Fr Stanley L Jaki, OSB, 1987, Trinity Communications, p 77].

The Swiss Calvinist biblical scholar, Oscar Cullman, declared …”the Roman Catholic exegesis must be regarded as correct.” (See* Peter, Apostle, Disciple, Martyr*, 1953, p 18-20).
Paul calls Peter “Cephas” quite often.
[Keating, p 208-11].

Cephas is Aramaic for Rock and Petra is the Greek. When he said, “You are Peter, and on this rock I will build my church,” the two words meant the same thing.

“What we really have is a spiral argument. On the first level we argue to the reliability of the Bible as history. From that we conclude an infallible Church was founded. Then we take the word of that infallible Church that the Bible is inspired. It reduces to the proposition that, without the existence of the Church, we could not tell if the Bible were inspired. As Augustine said, ‘I would not believe in the Gospel if the authority of the Catholic Church did not move me to do so.’ ”

So it emphatically is not circular. “We are not basing the inspiration of the Bible on the church’s infallibility and the Church’s infallibility on the word of an inspired Bible. That indeed would be a circular argument.”


A couple of things I want to say:

  1. The closest original source we have is Greek…whether it was written in Aramaic first and then translated into Greek doesn’t matter because we only have the Greek version and so let that be good enough to argue from.

  2. With that said though I still want to point out,… we have a strong clue that Christ said this in Aramaic from the very text itself…

Matthew 16:17

Jesus answered and said to him, “Blessed are you, Simon Bar-Jonah, for flesh and blood has not revealed this to you, but My Father who is in heaven.

“Bar” is not Greek

So however you want to read it…Greek or Aramaic, Peter is the rock!


And the demonstration of this linguistic claim is where, exactly?

Petra doesn’t always refer exclusively to a large rock. Just look at 1 Peter 2:8:
A stone(lithos) that will make people stumble, and a rock(petra) that will make people fall.

Here “petra” is understood by the context to mean a small stone which will make people trip, not a huge massive rock.

Sorry, but no. Look at the Greek, not the English: λιθος προσκομματος is “stone of stumbling” and πετρα σκανδαλου is “rock of offence”. That term for offence is in the Greek of Mt 13:41, “The Son of man shall send forth his angels, and they shall gather out of his kingdom all things that offend”, and Rom 16:17, “Now I beseech you, brethren, mark them which cause divisions and offences contrary to the doctrine which ye have learned; and avoid them”: it is not a reference to physically stumbling over a literal stone, but to spiritually stumbling.

Also, if Jesus really wanted to be clear about Simon Peter being a pebble, the Greek language has a distinct word for this as can be seen in the beginning of verse 8. (lithos = small stone).

Sorry, but this one is also incorrect. Λιθος is stone generally, including small, large, and the material from which things were built: it is used in Mt 21:44 for a stone heavy enough to crush someone to death, in Mt 28:2 (et al.) for the stone which blocks the entrance to Jesus’ tomb, and in Rev 18:21 for a “huge millstone”.

For a pebble/small stone, the Gospel writer could have used ψηφις, καχληξ, στια, or λιθιδιον, the last being the diminutive of λιθος. Using any of those, however, would have obstructed the πετρα / πετρος interplay which we have now.

There is only one word for “rock” in Aramaic and that word is “kepha”.

Really? This is a curious claim, given that the Aramaic Bible contains more than two dozen words for rock.

Cephas is Aramaic for Rock and Petra is the Greek.

Actually, in Greek there were plenty of choices for “rock”, but Πετρος was the better one for an individual person when paired with πετρα. Λιθος, also usually masculine and also used in 1 Pe 2:4 for the Lord and 1 Pe 2:5 for God’s people, would have blurred the connection to πετρα. Note also that Abp Sheen discriminates between πετρος and πετρα, following St. Paul in 1 Cor 10:4 in reading πετρα in Mt 16:18 as Christ.

When he said, “You are Peter, and on this rock I will build my church,” the two words meant the same thing.

This is theoretically possible for the Aramaic, but not for the Greek. If you imagine the Greek to be a corruption of the meaning, then you could claim that they meant the same thing, although that would rather complicate the representation of Scripture.

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