Actually, Cephas is just a different way to spell Kefas with the English alphabet.
As used in the New Testament, it is simply the transliteration of the Hebrew word "kefa."
Kefas only appears twice in the Hebrew Scriptures. It refers to a special kind of stone. It is not the same terms that are used to Figuratively speak of the characteristics of God. The Hebrew lexicons give the meaning "holow rock," FWIW.
Actually, Cephas is just a different way to spell Kefas with the English alphabet.
John 1:42
And he brought him to Jesus. And when Jesus beheld him, he said, Thou art Simon the son of Jona: thou shalt be called Cephas, which is by interpretation, A stone.
It is evident that even at that time the name meant stone or rock which in English is interpreted as Peter.
And it makes no difference if it means a small stone or a big one, that is only a play on words.
It appears to me that Peter did take the lead among the Apostles which was known by Jesus that he would.
At the same time i do not see any where that it says any thing about Peter being Pope.
The Papacy is religion and i can not see Jesus as thinking kindly toward religion.