An early extra-biblical story about St. Philip is preserved in the apocryphal Letter from Peter to Philip, one of the texts in the Nag Hammadi Library, and dated to the end of the 2nd century or early 3rd. This text begins with a letter from St Peter to Philip the apostle, asking him to rejoin the other apostles who had gathered at the Mount of Olives. Fred Lapham believes that this letter indicates an early tradition that at some point between the Resurrection of Jesus and the final parting of his risen presence from the disciples, Philip had undertaken a sole missionary enterprise, and was, for some reason, reluctant to return to the rest of the Apostles. This mission is in harmony with the later tradition that each disciple was given a specific missionary charge. Lapham explains the central section, a Gnostic dialogue between the risen Christ and his disciples, as a later insertion.