As a convert to the faith, the office of the papacy was explained like this. It makes perfect sense and I use it to this day when talking to anti-Catholics:
Many Protestants deny that Peter was ever in Rome. (See 1 Peter 5:12-14). But history tells us he was. Peter was crucified in Rome for his faith. (There is a reason the church is in Rome …Peter was buried in a place called Vatican Hill. When Constantine made Christianity legal, he gave this area to the Christians and a church was built there. St. Peter’s bones still lie at the Vatican.) Peter was crucified upside down because he did not want to detract from our Lord’s crucifixion. (I love the Caravaggio painting depicting this … )
Anyway, for the Biblical aspect.
First, read John 10:1-21 – This is the parable of “The Good Shepherd.” Read it and remember what Christ says.
Now, flip over to John 21:15-19. Jesus asks Simon three times if he loved him. After Simon replies “yes” each time Christ tells him to feed and tend Christ’s sheep.
In John 1:42, Christ does something interesting. He calls Simon to Him and CHANGES HIS NAME. He says, “You are Simon, son of John; you will be called Kephas.” Kephas, in Aramaic, the language of Christ, literally means ROCK, is translated into English as Peter. The Greek word for stone or rock is petros which is where we get Peter. (You gotta love etymology!) Neither Kephas, or the Greek Petros, is attested as a personal name before Christian times.
Ok, so Simon has a new name and a new mission … to tend and feed the flock.
Now go to **Matthew 16:13-20. **
*][FONT=Georgia]"Blessed are you, Simon son of Jonah. For flesh and blood has not revealed this to you, but my heavely Father. And so I say to you, your are Peter, and upon this Rock I will build my church and the gates of hell shall not prevail against it. I will give you the keys to the kingdom of Heaven. Whatever you bind on earth shall be bound in heaven; and whatever you loose on earth will be loosed in heaven. [/LIST][/FONT]
Quite literally, that passage says, “You are Kephas on on this Kephas I will build my church.” Remarkable, especially since the church IS built right on top of Old Kephas to this day… in more ways than one.