Nothing wrong there....And Simon Peter answered and said, Thou art the Christ, the Son of the living God..
I doubt that Jesus used the word "church" .. but OK, we get the gist. Jesus trusted him that he believed in him...thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it..
The Gospel according to Peter, is an ancient text concerning Jesus Christ, only partially known today. It is considered a non-canonical gospel and was rejected as apocryphal by the Catholic Church's synods of Carthage and Rome, which established the New Testament canon
..and naturally, we can't challenge the "Christian Bible" canon, now, can we.
The same Gospel was in use among the Ebionites, and, in fact, as almost all critics are agreed, the Gospel according to the Hebrews, under various names, such as the Gospel according to Peter, according to the Apostles, the Nazarenes, Ebionites, Egyptians, etc., with modifications certainly, but substantially the same work, was circulated very widely throughout the early Church
..so, we get the Holy Bible .. the Holy Qur'an .. the Holy Grail etc.
People are entitled to believe what they like .. such as Mary is the "mother of God" or the Bible canon was "written by God" etc.