Petros and Petra


Does anybody have any idea why in Matthew 16:18 there are two different forms of ‘Petros’?

Why did Jesus not say “You are Petros and on this Petros I will build my church”. Why is ‘petra’ used in the second instance?


There’s an ongoing discussion about this on another thread, particularly from post #13 onward:


Jesus spoke in Aramaic. In Aramaic Peter is Kepha. When the bible was translated into Greek Petra was changed to Petros. Petra means large rock. A metaphor for Peter being the first Pope.

Peter was the foundation on which Catholic Church was built. Jesus is the architect who started building the church on Peter. Jesus gave Peter authority over all the apostles.


Jesus spoke in Aramaic. When the bible was translated into Greek Petra was changed to Petros. Petra means large rock. Petra was changed to Petros because it was masculine at the time Matthew 16:18 was wrote. It was considered a insult to give the first pope a fiminine name.

Peter was the foundation on which Catholic Church was built. Jesus is the architect who started building the church on Peter. Jesus gave Peter authority over all the apostles.


So are you saying that it just would have been improper to use Petros twice? I get the masculine, feminine thing, but why couldn’t the masculine form be used twice?


Jesus is saying to Simon… You are a Rock and on this Rock I will build my Church.

It’s saying first that Jesus is calling Simon a Rock and secondly it is on the Rock of Simon that His Church will be built upon. We don’t often speak that way, in phrases like Jesus did, but they did back then when language wasn’t as developed.

Today we would say something like

Simon you are the Rock that my Church will be built upon.


I’m no linguistic expert but does it matter if they both come from the word Rock? One is referring to a person whom Jesus called Simon or a noun, the second is referring to what the Rock is in relationship to the Church, the earthly spiritual leader of the Church. I believe that people use this ‘Petra or Petros’ conversation as meaning Jesus distanced Himself from the people of the Church and find error in us believing in the role of the Pope/Peter being the Rock, but really if you look at it, Jesus did not… He still called it ‘my Church’… Meaning the Church belongs to Jesus Christ and furthermore Jesus is the Cornerstone of the Church. What wouldn’t have made sense is if Jesus said to Peter, You are Jesus, and on this Jesus, I will build My Church. It seems simply obvious grammatically to me what Jesus meant irregardless what form of Peter is used in scripture.:shrug:


Most protestants think that Petros means small rock. There point is that Jesus was a large rock and Petra was the small rock.

In the Catholic Church Peter is the foundation of the Church. It’s like Peter is the cornerstone of the Church and the rest of the Church is built on this cornerstone.

This is what I meant by Jesus is the architect who built the Church on Peter early in this thread.

Read this if you still don’t understand.


Because the Greek noun for “rock” is feminine, and therefore gets a feminine ending, -a. You could not use the masculine ending for this because the word itself is feminine. To force a masculine ending would render this ungrammatical.

In Greek, a man could not be named a feminine word, so in this case, the change to a masculine word ending is required, -os.

The issue does not exist in Aramaic, where the distinction in the case of “kepha” does not exist. The change is purely to keep within the rules of Greek grammar.


Be careful Jesus is the founder who laid the foundation of the Church with the Apostles and prophets and it is Jesus who is the cornerstone of the Church. So you see even though the Church began on the apostles which gave it a firm foundation (see Matthew 7:24-27) about Jesus teaching about firm foundations…And Jesus is the cornerstone not Peter. The following describes the Church.

Ephesians 2:19 Consequently, you are no longer foreigners and strangers, but fellow citizens with God’s people and also members of his household, 20 built on the foundation of the apostles and prophets, with Christ Jesus himself as the chief cornerstone.


Wait, isn’t Jesus the cornerstone.


You did’nt read what I said. I agree I probably should have been more specific on explaining myself.

A architect is someone who designs buildings and sees to that things get built right. I used architect as a metaphor for Jesus founding the Catholic Church. Peter was the spokesperson for Jesus just as the present pope is.


You did’nt read what I said. In know way am I offended.

A architect is someone who designs buildings and sees to that things get built right. I used architect as a metaphor for Jesus founding the Catholic Church. Peter was the spokesperson and first Pope for God just as the present pope is.


Actually I did read what you said and I figured you didn’t mean to say that Peter is the cornerstone so I pointed out to be careful, meaning about how you say things. To reiterate there is only one cornerstone and that is Jesus Christ and the Church would not be the architect were it not for the Holy Spirit and Jesus guiding them. This is not just a building, it’s a living organism as the body of Christ, and without Gods hand in it it could not have been built nor held together as it has been…Jesus has not left us, Jesus remains with us, in the Priests, when we Gather in His name, in the Eucharist, in the reading of The Word… Jesus is not apart from us, but remains with us always…I get that you’re staying the Pope is the spokesperson for Jesus, but were it not for Jesus being with them, teaching them and inspiring them, they could not do their job…


Petra us the noun for rock. It is feminine. In Greek, the word is pretty much locked into its gender. A male horse or a female horse, it doesn’t matter, the word horse has a gender, and that’s the gender you use for it when you’re using regular nouns for an animal of either gender. However, Petros wasn’t just the word for what Peter was, it was made his proper name, and in Greek it wouldn’t make sense for Peter to have a feminine name. The problem didn’t exist in Aramaic.

That said, people would have recognized that Petros was a masculine form of rock. The stem of the word is recognizable, and people would have recognized the masculine gender ending. It works as a name, but it wouldn’t make sense if you then used the word petros for a literal stone you hold in your hands. That would be improper Greek. If petros was used in both instances it wouldn’t work, and if petra was used in both instances it wouldn’t work. Koine Greek is not English. The way cases, gender, and number are used makes it very different. It also works differently than the romance languages I’m familiar with, like French and Spanish. I think any first year Greek student could attest to that.

Anyway, the difference is simply due to Greek grammar rules. It’s not significant in the way people who try to downplay Peter’s role claim it to be. The rest of the context of what Jesus says to Peter, and Peter’s obvious prominence throughout the Gospels, Acts, his mentions during the epistles, and early tradition, all are quite clear.


God is the Rock.

As St. Paul says, Christ is the Rock (as our song states: Rock of Ages/eternity).

Peter is a stone taken from the Rock’s quarry; Peter is of the same “nature.” We share in the divine nature, as St. Peter says in his epistle.

This is also why the walls of the Heavenly Jerusalem has a wall of stones.

Too much, but so what: this should be understood as precious stones.

(And gold and silver might have been seen as stones, but I do not know that for sure)

Sorry about too much.




No, petra does not definitively mean large rock.
The gender does not really change the size of the rock, or any of that nonsense that I regularly hear. There are instances of petros in Koine Greek, where the rock is explicitly too heavy to be lifted by even three very strong men.

Petros and Petra both refer to a kind of rock; a flinty rock. Size is pretty much irrelevant to the discussion. The gender issues, though, do appear to affect the passage.

On the other hand; Petra is a collective word, just as is water, day, and enemy. That also affects the passage.

But: Matthew 16:18 uses standard Greek grammar to explicitly tie both words for rock together into one item. Both Petros and Petra clearly refer to one and the same rock.

There are many examples in Koine Greek where a definite article is added to a collective word to indicate that it is being used as a singlton: eg: When a Greek author write “this the day” they explicitly mean, this very day (the same single, not collective, day already mentioned.)

In Matthew 16:18, the exact same grammatical structure is used.
Matthew wrote: You are petros (male rock), and upon this “THE” rock I will build my church.

By putting a definite article on a collective form, “petra”, Matthew indicates that he means a definite rock already spoken of. Since the only definite rock mentioned in that passage is “petros” (Peter); Jesus is clearly alluding to Peter being a rock among a collection upon whom Jesus intends to build his church (ekklesia).

Peter, being a Jew, is a rock dug from the quarry of Abraham every bit as much as the wealthiest Pharisee; God does not make distinctions based on wealth, or honor among men.

Rather, See Isaiah 51:1-2, and recognize that all true sons of Abraham were identified as “rocks”; eg: That historical perspective is exactly what John is referring to in Matthew 3:9 (same Gospel) when he says to the pharisees: “Don’t say to yourselves we have Abraham as our father, for God can raise sons to Abraham from these stones.”

The high and mighty have no privilege that makes rebuilding the promise of God out of a humble remnant from Abraham impossible; even if the common man is despised by the authorities who see only themselves as fit building material.

Peter is a very humble man, and Jesus clearly is building his church out of living stone of whom Peter was chosen first.


Huiou Theou #16

*No, petra does not definitively mean large rock.

Petros and Petra both refer to a kind of rock; a flinty rock. Size is pretty much irrelevant to the discussion. The gender issues, though, do appear to affect the passage*.

The reality here is well explained by Fr John Echert:

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.
[My emphasis].

The reality of Peter being the Rock on which Christ founded His only Church is exemplified by Peter’s the recognition of Peter’s status in Christ’s Church.

Already, Peter had exercised his supreme authority in the upper room before Pentecost to have Judas’ place filled. At the first Apostolic Council of Jerusalem Peter settled the heated discussion over circumcising the gentiles and “the whole assembly fell silent” (Acts 15:7-12). Paul made sure that his ministry to the gentiles was recognised by, Peter (Gal 1:I8).

From the N.T. we know that Christ promised that His Church would last until the end of time, which would mean the constitutional permanence of the office of head of His Church which He had bestowed on Peter alone. (Mt 16:18). Early Church history, e.g. St Irenaeus, taught by St Polycarp who had been a disciple of St John the Apostle, wrote in his great work Adversus Haereses in Bk 3, Sect 2 “The blessed Apostles, after founding and building up the Church (in Rome), handed over to Linus the office of Bishop.”

Peter often spoke for the rest of the Apostles (Mt 19:27; Mk 8:29; Lk 12:41; Jn 6:69). The Apostles are sometimes referred to as “Peter and his companions” (Lk 9:32; Mk 16:7; Acts 2:37). Peter’s name always heads the list of the Apostles (Mt 10:1-4; Mk 3:16-19; Lk 6:14-16; Acts 1:13). Finally, Peter’s name is mentioned 191 times, which is more than all the rest of the Apostles combined (about 130 times).


Fr. Echert is on solid ground with respect to Cepha and Petros. His conclusion is fine. However, your own statement is rather imprecise as an apologetic. You might want to consider the fact that in Matthew 16:18 both a masculine form (Petros) and a non-masucline form (Petra) are both being used to refer to the same man.

If, as an apologetic, it were strictly a masculine and feminine issue; then the word “Petros” would have been used twice. Anyone who actually studies the Greek, and looks at the grammar will eventually realize that Peter is spoken of as “masculine” in the first part, and “feminine” in the second part of the sentence. The common apologetic idea that a man “can not” be spoken of using the feminine form of “rock” simply isn’t true. For whether a person argues that the second “petra” means Peter, or Jesus himself, or all the twelve, or pick any male you want; the fact remains that the second use of the word “rock” is still feminine but still refers to men.

The issue which would be good for you to consider carefully is that collective nouns are always derived from the feminine in Greek; so whenever a collective is spoken of; even if the ‘thing’ is male; the collective form of the word can still be female.

In the passage of Matthew, Jesus can be understood to be referencing a collection of rocks in the second part of the sentence, while still using the grammar to single out ONE of those rocks. That’s why he uses the feminine. There is no equivalent grammar in English, so I would need to use a circumlocution to emphasize what Jesus said. I think a more precise, but perhaps awkward translation would be something like:

Matthew 16:18 but, I also say to you, "You are Rock, and on this very-same rock [out of many], I will build my [very-own] congregation, and Hade’s gates will not be strong under it.

Sometimes people want to translate “You are Rocky, and on this very-same rock…” in order to show a distinction of words with the same meaning; but that’s a bit forced kind of translation because “Rocky” is name calling, and name calling would typically be in a different declension (vocative) than is actually found in the Greek. I mean when Paul says to the high priest,“You white washed wall” – he actually says “Whitey!” (name calling).

Why Jesus doesn’t use the vocative, I don’t know. But he doesn’t, so translating “Rocky” would be going beyond what can be really found in the Greek.

Note: Congregation is typically understood as church, so “I will build my very-own church” is just as precise as translation as what I did.

The key to grasp is that when a definite article is used in a place where it does not translate into English as “the”; that’s typically an intensifier. eg: “The” means “very” or “Very-same” or “very-own” etc. When there is a combination of words “This the”, in Greek, what the author is doing is breaking up the following word from collective usage and letting the reader know that he means a particular item from within a group or amalgam.

For example, water is a collective. Saying “this the water”, would generally indicate a portion of water from a pool or perhaps one glass of water among many. “this the day” would indicate a particular day from some epoch or era. That’s the kind of idea that Jesus is alluding to: Peter, son of Abraham, a stone among many; Upon you, Peter, I will build my church (and not necessarily the others.)

In the case of Matthew 16:18, as you have noted, Peter is the first to be chosen; and is the leader of the rest. That’s a very good explanation of what is implied by Jesus noticing that there are other stones besides Peter, but still choosing to single him out alone from all the rest in this one passage.

It’s not that Jesus will not also use the other apostles as building stones later, for Revelation has a description of the temple which tells us that the other apostles were also used; rather, Jesus is preferring Peter here, explicitly over and above the rest of the group of all possible “stones.”

There is no reason for Jesus to have used “Petra” otherwise. The sentence could have been constructed with a Generic “you”, eg “and upon you I will build my very church.”

By going out of his way to reference the idea of rock a second time, (and in the feminine), Jesus is showing and emphasizing that Peter is chosen and preferred.
He is “first” among his brothers.

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