I cannot believe that the Church was founded upon Peter, If was built upon Christ, who is the true foundation stone.

The Catholic Answers

No one claims that St. Peter was the principal foundation stone. But that Church which is in communion with St. Peter and his successors is the genuine Church built upon the foundation of Christ. Christ Himself said to Peter, “Thou art Peter, and upon this rock I will build my Church.” Christ is the solid rock upon which the Church is built. But the first rock laid upon thi9 foundation is Peter, Christ being the principal foundation stone, Peter being the secondary foundation chosen by Christ.

Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty