Some things I’d like to point out…
“You are Peter, and on this rock I will build my Church” (Matt. 16:18). Disputes about this passage have always been related to the meaning of the term “rock.” To whom, or to what, does it refer? Since Simon’s new name of Peter itself means rock, the sentence could be rewritten as: “You are Rock and upon this rock I will build my Church.” The play on words seems obvious, but commentators wishing to avoid what follows from this—namely the establishment of the papacy—have suggested that the word rock could not refer to Peter but must refer to his profession of faith or to Christ.
From the grammatical point of view, the phrase “this rock” must relate back to the closest noun. Peter’s profession of faith (“You are the Christ, the Son of the living God”) is two verses earlier, while his name, a proper noun, is in the immediately preceding clause.
As an analogy, consider this artificial sentence: “I have a car and a truck, and it is blue.” Which is blue? The truck, because that is the noun closest to the pronoun “it.” This is all the more clear if the reference to the car is two sentences earlier, as the reference to Peter’s profession is two sentences earlier than the term rock.
Look at the Aramaic
Opponents of the Catholic interpretation of Matthew 16:18 sometimes argue that in the Greek text the name of the apostle is Petros, while “rock” is rendered as petra. They claim that the former refers to a small stone, while the latter refers to a massive rock; so, if Peter was meant to be the massive rock, why isn’t his name Petra?
Note that Christ did not speak to the disciples in Greek. He spoke Aramaic, the common language of Palestine at that time. In that language the word for rock is kepha, which is what Jesus called him in everyday speech (note that in John 1:42 he was told, “You will be called Cephas”). What Jesus said in Matthew 16:18 was: “You are Kepha, and upon this kepha I will build my Church.”
When Matthew’s Gospel was translated from the original Aramaic to Greek, there arose a problem which did not confront the evangelist when he first composed his account of Christ’s life. In Aramaic the word kepha has the same ending whether it refers to a rock or is used as a man’s name. In Greek, though, the word for rock, petra, is feminine in gender. The translator could use it for the second appearance of kepha in the sentence, but not for the first because it would be inappropriate to give a man a feminine name. So he put a masculine ending on it, and hence Peter became Petros.
Furthermore, the premise of the argument against Peter being the rock is simply false. In first century Greek the words petros and petra were synonyms. They had previously possessed the meanings of “small stone” and “large rock” in some early Greek poetry, but by the first century this distinction was gone, as Protestant Bible scholars admit (see D. A. Carson’s remarks on this passage in the Expositor’s Bible Commentary, [Grand Rapids: Zondervan Books]).
…Consider another point: If the rock really did refer to Christ (as some claim, based on 1 Cor. 10:4, “and the Rock was Christ” though the rock there was a literal, physical rock), why did Matthew leave the passage as it was? In the original Aramaic, and in the English which is a closer parallel to it than is the Greek, the passage is clear enough. Matthew must have realized that his readers would conclude the obvious from “Rock . . . rock.” …
Why is there misunderstandings with all of the non-Catholics?