Actually, in the original manuscripts of the NT and in the earliest manuscripts of Matthew's Gospel, ALL Greek letters are in all caps. There was no distinction between uppercase and lowercase letters in Greek until the Greek miniscule script was invented in the 9th century A.D.
Also, regarding petros vs. petra, these sometimes (mainly when used in poetry) conveyed nuances differences in the older Attic form of Greek that was used from about the 5th to 3rd century B.C., but these words were synonymous in the Koine Greek of the NT era, as pointed out by knowledgeable Protestant commentators such as Baptist New Testament professor Donald A. Carsons III in the Expositors Bible Commentary Volume 8: "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 dubious at best; 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."" Jesus' wordplay only makes sense in Greek or in English if his back-to-back uses of "rock" and "this rock" both refer to Peter. As Carsons puts it in the Zondervan NIV Bible Commentary, "if it were not for Protestant reactions against extremes of Roman Catholic interpretations, it is doubtful whether many would have taken 'rock' to be anything or anyone other than Peter."
As Carsons puts it in the Zondervan NIV Bible Commentary, “if it were not for Protestant reactions against extremes of Roman Catholic interpretations, it is doubtful whether many would have taken ‘rock’ to be anything or anyone other than Peter.”
I think Carsons explains it pretty well when using the term the “extremes” of Catholic interpretations. This is but one of many.
Can’t wait to hear indulgences explained. Again more unbiblical teaching from the “infallible” pope no less.
We won’t even touch the current issue of molestation within the Church either.