As early as the mid-third century, there was evidence of the tradition to honour these two saints together. Peter (originally named Simon), a humble Galilean fisher, was on of the 12 apostles and was called by Jesus to "feed my sheep" as the Church's first pope. Paul (originally named Saul) had a miraculous encounter with the risen Jesus that led to his dramatic conversion, and he would become "Apostle of the Gentiles" and author of many New Testament letters.

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