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The word for Peter and for rock in the original Aramaic is one and the same; this renders it evident that the various attempts to explain the term "rock" as having reference not to Peter himself but to something else are misinterpretations...

... Objections. The meaning of this passage does not seem to have been challenged by any writer until the rise of the sixteenth-century heresies...
Catholic Encyclopedia

First question: Is the Catholic Encyclopedia an authoritative rule of faith?

Second question: What is this, "...in the original Aramaic..." thing? The inspired text was written in Greek, and in the real text (the Greek one, not the imaginary one) two different words are used, not "one and the same" word.

Furthermore, the attempt to characterize various explanations of the term "rock" as having reference not to Peter himself but to something else, and as "misinterpretations" unknown to anyone before the 16th century is refuted by Augustine:

...Why have I wanted to make this little introduction? In order to suggest to you that in Peter the Church is to be recognized. Christ, you see, built his Church not on a man but on Peter's confession. What is Peter's confession? 'You are the Christ, the Son of the living God.' There's the rock for you, there's the foundation, there's where the Church has been built, which the gates of the underworld cannot conquer.
Sermons, Volume III/6, Sermon 229P.1, p. 327.
...In a passage in this book, I said about the Apostle Peter: 'On him as on a rock the Church was built.'...But I know that very frequently at a later time, I so explained what the Lord said: 'Thou art Peter, and upon this rock I will build my Church,' that it be understood as built upon Him whom Peter confessed saying: 'Thou art the Christ, the Son of the living God,' and so Peter, called after this rock, represented the person of the Church which is built upon this rock, and has received 'the keys of the kingdom of heaven.' For, 'Thou art Peter' and not 'Thou art the rock' was said to him. But 'the rock was Christ,' in confessing whom, as also the whole Church confesses, Simon was called Peter. But let the reader decide which of these two opinions is the more probable.
The Retractations Chapter 20.1.

Cordially,

The inspired text was written in Greek, and in the real text (the Greek one

We don't know that, actually. The "inspired text" is whatever Matthew originally penned. Tradition indicates he wrote it in "Hebrew" (which may mean Aramaic, but certainly doesn't mean Greek).

An Aramaic/Syriac textual tradition of Matthew still exists, called the Peshitta. (Whether it's based on an Aramaic original, or the Aramaic original, is not clear.)