I have recently stumbled upon a protestant claim which appears to debunk that assertion: Protestants assert that in 1 Corinthians, Christ is described as the cornerstone using the word Petra, the feminine form of the word Rock.
How can one argue over masculine and feminine distinctions if the feminine form was used in reference to Christ?
Are you interested in the truth?
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.