In teaching the RCIA, I have been asked many questions by people with Protestant backgrounds especially about Peter's role and why Catholics believe that the pope is Peter's successor.
The key to Peter and his role are the words of Christ in Matthew (16.18-19): " You are Peter and upon this rock I will build my Church and the gates of hell will not prevail against it. I will give you the keys of the kingdom of heaven and whatever you bind on earth will be bound in heaven and whatever you loose on earth will be loosed in heaven."
Protestants sometimes claim that Jesus meant that he himself was the rock upon which the Church was to be built because it follows Peter's declaration, "You are the Christ, the Son of God."
Protestants sometimes say that what Jesus said was that Peter was "petro" or a small stone, while he, Christ, was "Petra," a great rock upon which he, Christ, would build the Church. But the Greek "Petra" is a feminine noun and so "petro," the masculine form was used for the man, Peter.
However, Jesus would have used the Aramaic "kappa" or Cephas which is the same word for a name and for a rock. At his first meeting with Peter, Jesus referred to Peter's future name as Cephas (John 1.42).
Peter is clearly shown as a primary player at the beginning of the Church, in the Gospels and in the Epistles. In addition, Jesus reiterated Peter's role after the resurrection when he singled out Peter, giving him an opportunity to declare his love before telling him to feed the lambs, tend and feed the sheep (John 21.15-17).
Peter remained as the foremost disciple throughout Jesus' ministry. Peter is named first in the list of three who accompany Jesus on special occasions such as the Transfiguration and the Agony in the Garden. It was into Peter's boat that Jesus embarked to preach (Luke 5.3). It was Peter whom Jesus called to walk on the water (Matthew 14.28).
It was Peter whom Jesus sent to catch the fish in whose mouth he found the coin to pay the tribute (Matthew 17.24). It was to Peter that Christ came first when washing feet at the Last Supper. It was Peter who took out his sword to defend Jesus when the soldiers arrived to take him.
Frequently, Jesus addressed Peter specifically, telling him to strengthen the others: "Simon, Satan has demanded to sift all of you like wheat but I have prayed for you that your own faith may not fail; and you once you have turned back strengthen your brothers" (Luke 22.32).
Peter often responded for all the apostles as when Jesus asked the apostles, "Who do you say that I am?"
After the resurrection, the women at the tomb were told: "Go tell his disciples and Peter" (Mark 16.7). The only disciple to whom Jesus appeared on the first day was Peter (Luke 24.34; 1 Corinthians 15.5). It would be hard to deny that Peter played a primary role during Christ's public ministry.
But he also continued to do so in the early Church. After Pentecost, it was Peter who delivered the first public sermon about Jesus converting large numbers (Acts 2.14-41). Peter was recognized as the head of the Jerusalem community until his missionary journeys, then being replaced by James.
Peter continued to take the leading role in the Church, travelling to various centres. It was Peter who took the initiative to select someone to replace Judas (Acts 1. 15). Paul went to Jerusalem to touch base with Peter (Galatians 1.18-20).
We don't know when Peter went to Rome but the historian, Eusebius (260-340) and early Church thinkers testified to Peter's presence in Rome as head of the Church. Never did any of them designate any other city but Rome as the site of Peter's martyrdom. They who were much closer to the apostles in time and background would be closer to the truth of events.
Would Jesus have given Peter all this authority – the keys of the master-steward, the binding and loosing, the feeding of the lambs and sheep, the strengthening of his brothers - to last only for the time of his mortal life without concern for the future of the Church?
When commissioning his followers to spread his message, to teach and to baptize, making disciples of all nations, he promised that he would be with the Church until the end of time (Matthew 28.19). What greater assurance can we have?
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