Roman Catholics believe that Christ appointed Peter to be the head of His Church. Peter was therefore the first Pope and all subsequent Popes successors of Peter.
Matthew 16:1819 18 And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it. 19 And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven. (KJV)
We know that Christ changed Simon’s name to Peter, which means “rock” and declared that He will build His Church on this “rock”. Christ also gave Peter the keys of the kingdom of heaven, and the Catholics believe that these denote His supreme authority.
Luke 22:3132 (NIV) “Simon, Simon, Satan has asked to sift you as wheat. 32 But I have prayed for you, Simon, that your faith may not fail. And when you have turned back, strengthen your brothers.”
In this verse, Christ specifically instructed Peter to strengthen his brothers indicating that Peter is chief over the other disciples.
Peter also acted as the chief in the assembly to choose Mathias as the new disciple (Acts 1:1522) and in the opening of the first Council of Jerusalem (Acts 15:7).
It is simple history that Peter went to Rome about the year 43 A.D., went back to Jerusalem after a few years for a short time and then returned to Rome until his death, except for very short absences. Papias wrote in 140 A.D., “Peter came and by his salutary preaching of the Gospel and by his keys opened in the City of Rome the gates of the heavenly kingdom.” Since Peter was the head of the Church and was in Rome most of the time, Roman Catholics regard him as the first Pope.
Protestants believe that Christ, and not Peter, is the head of the church.
Colossians 1:18 (NIV) And he is the head of the body, the church; he is the beginning and the firstborn from among the dead, so that in everything he might have the supremacy.
Ephesians 5:23 (NIV) For the husband is the head of the wife as Christ is the head of the church, his body, of which he is the Savior.
Mt 16:1819 has often been misunderstood. Jesus did not say to Peter, “upon thee I will build My church” but “upon this rock”. When Jesus said “this rock”, he referred to Himself whom Peter had acknowledged earlier in verse 16.
Matthew 16:1518 15 He saith unto them, But whom say ye that I am? 16 And Simon Peter answered and said, Thou art the Christ, the Son of the living God….18 And I say also unto thee, That thou art Peter (in Greek, Petros), and upon this rock (in Greek, Petra) I will build my church; and the gates of hell shall not prevail against it. (KJV)
In the Greek, the term for Peter is “Petros” (masculine gender) while the term for rock is “Petra” (feminine gender). The use of two different words “Petros” and “Petra” clearly proves that Christ was not referring to Peter. Some people maintained that looking at the Greek words is of no use since the book of Matthew was most probably written in Aramaic before being translated in Greek. This reasoning is faulty because the distinction of gender in Greek proves that there was a similar distinction in Aramaic. If there was no distinction originally, why was one made in Greek?
Even Paul says that “the rock (Petra) was Christ” (1 Cor 10:4). Elsewhere, Paul declares that Christ is the only foundation of a believer.
1 Cor 3:11 For other foundation can no man lay than that is laid, which is Jesus Christ. (KJV)
As to the keys of heaven given to Peter, Jesus gave the same thing (symbolized by the keys) to His other disciples.
Matthew 18:18 (NIV) “I tell you (plural, to all the disciples) the truth, whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven.
Similarly, the fact that Peter was asked to strengthen his brethren (Luke 22:31) in no way proves that he is chief. The Bible also speaks of apostles like Paul and Timothy (who are not Popes) as strengthening their brethren. (Rom 1:11, 1 Thess 3:2)