Updated: Dec 10, 2021
By Luke Lancaster
Jesus said, "You are Peter, and on this rock I will build my church" (Matthew 16:18). This notion has startling implications for the office of the papacy. Yet, many of our Protestant brothers and sisters will claim that Peter is not the rock of the Church. They say this as a reaction against the Catholic claims of the papacy, and in an attempt to discredit it. Catholics will point out that Peter's name means "rock," so Peter is the rock. Non-Catholic Christians will respond to this by quoting the original koine Greek text to Catholics. They will note that the word for "rock" is different than the word for "Peter." However, contemporary Protestant scholars have debunked this theory.
Unfortunately, non-Catholic Christians will still tell the tale that the Greek word for "Peter" is "Petros," and that the Greek word for "rock" is "Petra," so it is impossible for Peter to be the rock. Petros means small rock, and Petra means large rock. Peter is not the large rock upon which the Church is built, rather, Peter is simply a small rock like any other apostle. Modern, conservative, Protestant scholarship has rejected this theory, however, noting that the distinction in Greek between "Petros" and "Petra" was principally from poetic Greek literature from the 8th - 4th centuries BC.
According to these scholars, Jesus originally spoke Aramaic to his uneducated apostles. Aramaic does not have a distinction for "rock." The word just means "rock." So, Jesus would have said to Peter, "You are Rock, and on this rock I will build my Church." Notice the obvious wordplay - Peter is the Rock. The Greek words for "Peter" and "rock" are actually just the masculine and feminine version of the same words for "rock." Read three Protestant scholars' quotations below:
Professor of New Testament at Asbury Seminary, Dr. Craig Keener, said of the terms Petros and Petra: "In Greek here, they are cognate terms that were used interchangeably by this period" (IVP Bible Background Commentary of the New Testament, p. 90).
Professor of New Testament at Wheaton University, Dr. D. A. Carson, said, "Although it is true that petros and petra can mean 'stone' and 'rock' respectively in earlier Greek, the distinction is largely confined to poetry. Moreover, the underlying Aramaic is in this case unquestionable; and most probably kepha was used in both clauses ('you are kepha' and 'on this kepha'), since the word was used both for a name and for a 'rock.' The Peshitta (written in Syriac, a language cognate with Aramaic) makes no distinction between the words in the two clauses. The Greek makes the distinction between petros and petra simply because it is trying to preserve the pun, and in Greek the feminine petra could not very well serve as a masculine name" (The Expositor’s Bible Commentary, 8:368).
Professor of New Testament at the University of Oxford, Dr. R.T. France, said, "It is sometimes suggested that because the word for 'rock' (petra) differs from the name Petros, the 'rock' referred to is not Peter himself but the confession he has just made of Jesus as Messiah. In Aramaic, however, the same term kefa would appear in both places; the change in Greek is due to the fact that petra, the normal word for rock, is feminine in gender, and therefore not suitable as a name for Simon! The echo of Peter's name remains obvious, even in Greek; he is the rock, in the sense outlined above" (New Bible Commentary, 925-926).
For the sake of brevity, only three quotations were examined. Check out this Catholic site who compiled many more. They all say the same thing: Jesus was speaking Aramaic, in Aramaic there is zero distinction for "rock," Matthew's Gospel has a distinction only in terms of masculine and feminine forms for "rock."