Although Peter is one of the most prevalent people found in the New Testament writings and in the life of Christ, many non-Catholic Christians overlook his importance or tend disregard him as important all together. Christ and the New Testament writings make it very clear that Peter is not only important in the life of Christ but also the continuation of His Church.
We can see clear evidence of the importance of Peter and the significant role he would play in the early Church (and his successors for years to come) in the book of Matthew chapter 16. Verses Matthew 16:18-19 to be exact. These verses are nothing new to Catholic apologists and non-Catholic apologists. In Matthew 16:18-19, Christ changes Peter's name to Rock and defines his role/position/authority of Christ's Church here on Earth.
Matthew 16:18-19 says, "'And so I say to you, you are Peter, and upon this rock I will build my church, and the gates of the netherworld 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 shall be loosed in heaven'".
Christ in these verses makes it very clear that He is changing Simon's name to Peter and along with this name change comes the definition of Peter's role in the Church. In these verses, Christ calls and changes Simon's name to Peter which means 'Rock'. The name change is significant because following the re-naming, Christ explains that on this 'rock' He will build His Church. To Catholics (and some Protestant Christians), they understand that Christ is explaining to Peter that He will build His Church on the 'rock' that is Peter. Although this teaching seems clear, there are still some non-Catholic Christians who believe that Peter is not the 'rock'. But why is that? A common reason is that they believe Peter can NOT be the 'rock' in Matthew 16:18 if Christ is referred to as the 'cornerstone' in verses such as Ephesians 2:19-20, 1 Peter 2:4-9, and 1 Corinthians 10:4.
Although Christ is referred to as 'rock'/'cornerstone'/'capstone' in these verses, this does NOT mean that Peter cannot be the 'rock' in which Christ promised to build His Church. The two, Jesus and Peter, being called 'rock' (or some variation of the term) does NOT take away from the other's position. One thing that we should note is that Christ himself is the one who changed the name of Simon to Peter (meaning 'rock'). Peter did NOT change his OWN NAME, but Christ DID. And why did Christ do this? To show the important role that Peter would play in the Church of Christ.
There are three main points that we are going to go over to explain the position that Peter can be the 'rock' in Matthew 16:18-19, all while Christ still remains as the 'cornerstone'. The three points are: the title of 'rock' is given to others in Scripture, the Good Shepherd (a.k.a. Christ) gives Peter the role of Shepherd, and lastly, Christ affirms that Peter's name means 'rock' elsewhere in Scripture.
Main Point #1: There are others in Scripture that are called 'rock'.
Christ and Peter are not the only ones in Scripture that are called or referred to as 'rock'. God in the Old Testament is referred to as 'rock' in verses such as Isaiah 44:8. Abraham is also referred to as 'rock' in the Old Testament writings in verses such as Genesis 17:5. God, Jesus Christ, Abraham and Peter all being called 'rock' does NOT take away from any of them being the 'rock' in those verses. If we hold to the non-Catholic view that if Christ is the rock, than Peter CANNOT be the rock, then we must also deny the 'rock' title to Our Father in Heaven and Abraham. However to deny any this title of 'rock' would be 1. contradicting what the Word of God says and 2. would not take away from the authority/role/position that comes along with the name of 'rock'.
Main Point #2: Christ, the Good Shepherd, gives Peter the role of Shepherd
In Scripture, Christ refers to Himself as the Good Shepherd in verses such as John 10:11-15.
"I am the good shepherd. A good shepherd lays down his life for the sheep. A hired man, who is not a shepherd and whose sheep are not his own, sees a wolf coming and leaves the sheep and runs away, and the wolf catches and scatters them. This is because he works for pay and has no concern for the sheep. I am the good shepherd, and I know mine and mine know me, just as the Father knows me and I know the Father; and I will lay down my life for the sheep." (John 10:11-15)
However, this Good Shepherd gives special roles and authorities to Peter which are characteristics of a Shepherd in verses such as John 21:15-19.
When they had finished breakfast, Jesus said to Simon Peter, “Simon, son of John, do you love me more than these?” He said to him, “Yes, Lord, you know that I love you.” He said to him, “Feed my lambs.” He then said to him a second time, “Simon, son of John, do you love me?” He said to him, “Yes, Lord, you know that I love you.” He said to him, “Tend my sheep.” He said to him the third time, “Simon, son of John, do you love me?” Peter was distressed that he had said to him a third time, “Do you love me?” and he said to him, “Lord, you know everything; you know that I love you.” [Jesus] said to him, “Feed my sheep. Amen, amen, I say to you, when you were younger, you used to dress yourself and go where you wanted; but when you grow old, you will stretch out your hands, and someone else will dress you and lead you where you do not want to go.” He said this signifying by what kind of death he would glorify God. And when he had said this, he said to him, “Follow me.” (John 21:15-19)
Peter being given the role of shepherd to tend and feed the flock of Christ does NOT take away from Christ being the 'Good Shepherd". Christ Himself passes on this role to Peter, similarly to how Christ gives Peter the authority to "bind" and "loose" things on Earth (Matthew 16:18-19). When Christ changed Simon's name to Peter in Matthew 16:18-19, he also gave Peter special roles on Earth just as he did in John 21:15-19 when Christ calls on Peter to tend his flock.
Main Point #3: Christ affirms that Peter's name means 'rock'
Christ, HIMSELF, affirms the teaching that Peter means 'rock' in other places in Scripture. Verse John 1:42 to be exact. In John 1:42, prior to the name change of Simon to Peter, Christ makes a promise to Simon.
Then he brought him to Jesus. Jesus looked at him and said, “You are Simon the son of John; you will be called Cephas” (which is translated Peter).
Christ promises Simon he would change his name to Cephas, which he fulfills in Matthew 16:18. The word/term "Cephas" is a transliteration of the Aramaic word Kepha. Kepha is the Aramaic word for 'Rock". During these times, Christ and his apostles would have been seen speaking in Aramaic. We also can confirm this by looking at verses such as Matthew 27:26 where Christ is dying on the cross.
And about three o’clock Jesus cried out in a loud voice, “Eli, Eli, lema sabachthani?”[ab] which means, “My God, my God, why have you forsaken me?”
In this verse, Christ is seen speaking Aramaic. Combining our understanding when Christ was referring to Peter as 'rock' in Matthew 16:18 and 'kepha' in John 1`:42, we can affirm our understanding that Christ was calling Peter 'rock'.
Peter being the 'rock' in Matthew 16:18, does NOT take away from Christ being the 'rock', instead it helps us as Christians further understand how Christ intended for His Church to be and the authority given to it. Christ did NOT leave His Church without guidance or authority. He left His Church with authority that has remained with it for nearly 2000 years.
Interestingly enough, one of the verses mentioned at the beginning of the article, that is often used to 'contradict' the teaching of Peter being the Rock, Ephesians 2:19-20, actually affirms our understanding of the authority Christ gave to the Church.
Ephesians 2:19-20 says:
So then you are no longer strangers and sojourners, but you are fellow citizens with the holy ones and members of the household of God, built upon the foundation of the apostles and prophets, with Christ Jesus himself as the capstone.
This verse explains that the foundation of the household of God is the apostles and the prophets. The apostles and the prophets being the foundation does NOT take away from Christ being the 'capstone', but instead affirms Christ's intentions for His Church on Earth.
Peter being the rock, does NOT take away from Christ being the "cornerstone".