Christians in many traditions celebrate on January 18 the “Confession of St. Peter”, or “The Good Confession”:

When Jesus came into the coasts of Caesarea Philippi, he asked his disciples, saying, Whom do men say that I the Son of man am?
And they said, Some say that thou art John the Baptist: some, Elias; and others, Jeremias, or one of the prophets.
He saith unto them, But whom say ye that I am?
And Simon Peter answered and said, Thou art the Christ, the Son of the living God.
And Jesus answered and said unto him, Blessed art thou, Simon Barjona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven.
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.
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.
(Matthew 16: 13-19, Holy Bible, King James Version)

Peter’s statement, which is subsequently praised by Jesus, is a breathtaking pronouncement of Jesus’ exalted status. It has been used and repeated by Christians down the centuries as a kind of “credo”, and in a broad sense Peter speaks for the Twelve as well as all of us here. (As recently as last year, I have witnessed this used in Evangelical churches as a profession of faith at the time of baptism). Here, Jesus is identified by Simon as “the anointed one” (the awaited “messiah”), and also “the son of God”.

Jesus turns about and gives the disciple a fresh identity, and engages in a bit of a pun. Simon was from henceforth to be “Peter” (“Πέτρος” meaning “stone”), and declares that his community of believers would be founded upon this rock (“πέτρᾳ” or “boulder”). One strand of interpretation has been to identify the church as being founded upon Simon Peter. The foundation stone is more likely not Peter himself but rather his confession, his belief.

In the words of one Dr. James Boyce, Professor emeritus of Greek and New Testament at Luther Seminary, St. Paul, MN:

Peter speaks for the disciples, for Matthew’s gospel and the community to which it is first addressed, and certainly for us, announcing that Jesus is the Messiah, the Son of the Living God (16:15-16). Jesus confirms this “confession” by Peter as a mark of God’s blessing and as the “rock” upon which he will build his church (16:17-18).
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