In the simpliest of terms,can someone please explain the breakdown of Matt16 when Jesus changes Peters name to the Rock. This topic is going to come up about the differences between petra and petros and I have a hard time following the discussion when it gets into that (its all greek to me:D)

** Thanks**

Basically, Jesus changed Simon’s name to “Cepha”, (the Aramaic term for rock"), as is evidenced in the rest of the NT, in which “Cepha” is also used instead of “petros”.

It was rendered in Greek as “petra” & “petros” due to the grammatical structure of the Greek the gospel was first translated to.

In any case, here are a couple of good articles on the subject:


In the simplest of terms as requested, Jesus says…
18 And I say to thee: That thou art Rock; and upon this rock I will build my church, and the gates of hell shall not prevail against it.

All the arguing about Peter-Petros-Petra is just people trying to justify the teaching of their “church” which doesn’t allow for Christ to have set up an authority on earth for the shepharding of His people. Their point is moot because, as previously stated, Jesus would have been speaking Aramaic and called him Cephas, which is translated as Rock.

This is the first thing I looked up when I finally was tired enough of the churches I was going to and their inabikity to agree on scripture concerning a doctrine. The big argument was the term “rock” in this verse and who it exactly meant.

I went down to a library and asked for a hebrew and aramaic dictionary. I looked op the term kephas and cephas and what did I find? It meant rock, and sometimes large or massive rock/stone.

This was the beginning of my investigation into early church history. I figured that if these “bible churches” as they called themselves, could get this aspect of scripture wong, then I could no longer trust their perspective on scripture. I decided that I would have to get as close to the source as possible in order to see how the very early church looked at these verses and others.

I’m currently in a bit of an ongoing debate with my non-denom boyfriend about this. According to him, when Jesus says that “upon this rock I will build my Church,” the “rock” is not Peter, but the revelation of Jesus as the Christ that Peter said. Therefore, Peter is not the Pope or the head of any organized “institution,” just one of the Apostles. There is no universal organized church being founded, just the church, the whole Body of Christ meaning people who believe that Jesus is the Christ as Peter had stated.

I asked him why Jesus would change Simon’s name to Peter if it had no meaning immediately after, if Jesus was going to really mean that the revelation was the rock? Why wouldn’t He have been clearer? My boyfriend says that he can understand why Catholics would “mistakenly” believe that Jesus was referring to Peter, but that he’s kind of disturbed that I can’t understand what he believes. Trying to explain Church authority and the papacy and hierarchy from a scriptural standpoint reaches an impasse when the first point can’t get through.

BTW, any comments about dating a non-Catholic can be kept out of this thread, thank you. If you want to get into that, you can start another thread or PM me. :slight_smile: And I know there are some that believe very, very strongly against it.

As a convert to the faith, the office of the papacy was explained like this. It makes perfect sense and I use it to this day when talking to anti-Catholics:

Many Protestants deny that Peter was ever in Rome. (See 1 Peter 5:12-14). But history tells us he was. Peter was crucified in Rome for his faith. (There is a reason the church is in Rome …Peter was buried in a place called Vatican Hill. When Constantine made Christianity legal, he gave this area to the Christians and a church was built there. St. Peter’s bones still lie at the Vatican.) Peter was crucified upside down because he did not want to detract from our Lord’s crucifixion. (I love the Caravaggio painting depicting this … )

Anyway, for the Biblical aspect.

First, read John 10:1-21 – This is the parable of “The Good Shepherd.” Read it and remember what Christ says.

Now, flip over to John 21:15-19. Jesus asks Simon three times if he loved him. After Simon replies “yes” each time Christ tells him to feed and tend Christ’s sheep.

In John 1:42, Christ does something interesting. He calls Simon to Him and CHANGES HIS NAME. He says, “You are Simon, son of John; you will be called Kephas.” Kephas, in Aramaic, the language of Christ, literally means ROCK, is translated into English as Peter. The Greek word for stone or rock is petros which is where we get Peter. (You gotta love etymology!) Neither Kephas, or the Greek Petros, is attested as a personal name before Christian times.

Ok, so Simon has a new name and a new mission … to tend and feed the flock.

Now go to **Matthew 16:13-20. **

*][FONT=Georgia]"Blessed are you, Simon son of Jonah. For flesh and blood has not revealed this to you, but my heavely Father. And so I say to you, your are Peter, and upon this Rock I will build my church and the gates of hell 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 will be loosed in heaven. [/LIST][/FONT]
Quite literally, that passage says, “You are Kephas on on this Kephas I will build my church.” Remarkable, especially since the church IS built right on top of Old Kephas to this day… in more ways than one.

God does not change the names of His followers for no reason at all. Take, for example the changing of Jabob’s name to Isreal in Genesis 35.

good for you, that was exactly my train of thought when i was investigating, although i never actually got to a hebrew/aramaic source. i wanted to get as close to the source as possible, no BS, no if’s and’s or butt’s, the cold hard truth. (then i realized that one could still question it no matter how deep you go, so it just comes down to faith again.)

so ya it does boggle the mind why protestants don’t do this as well, since imo, it’s the single most significant factor in establishing the authority of the Church. :shrug:

imagine bringing a stack of dictionaries and signed verifications from qualified professors to a protestant to see what they say…

Did I read this correctly, that the New testament was translated in attic greek from koine greek and there was no such word as petros in koine greek:confused:

If I’m understanding your question correctly, I think you misread it


“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.

Attic Greek had died out by the time of Jesus, if I remember correctly.

The Koine term for small rock is Lithos as the previous poster said. Lithos is used over 17 time in the NT for small rock. It’s even used a couple times for a larger rock, If I heard Marcus Grodi correctly.

Petros is simply the masculine gender for rock.

Incidentally, one Protestant minister claimed that “petros” came back into vogue for about 100 years during Christ’s time, and then faded away again.

Now THAT’S mental gymnastics!!!

you can find the best, “non-partisan”, linguistic research on Peter Petros Petra Kephas at’

Seriously good stuff, with references and sources, and it’s just linguistic research - not trying to prove a point, one way or the other…

I find Jimmy Akin’s explanation of Matthew 16:18, in his article on The Papacy: God’s Gift to the Church, pretty easy to follow.

I’ll second that one Todd…great suggestion.

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