In the first half of the second century, Papias of Hierapolis wrote a five volume treatise called Exposition of the Lord's Reports (κυριακῶν λογίων ἐξηγήσις; kyriakôn logiôn exêgêsis), now lost except for quotations preserved by Eusebius. Presbyter John (or John the Elder) is the named source for at least part of Papias's report about the composition of Mark.
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| 15 καὶ τοῦθ' ὁ πρεσβύτερος ἔλεγεν· Μάρκος μὲν ἑρμηνευτὴς Πέτρου γενόμενος, ὅσα ἐμνημόνευσεν, ἀκριβῶς ἔγραψεν, οὐ μέντοι τάξει τὰ ὐπὸ τοῦ κυρίου η λεχθέντα ἢ πραχθέντα. | 15 And this the presbyter would say: Mark, who was indeed Peter's interpreter, accurately wrote as much as he remembered, yet not in order, about that which was either said or did by the Lord. |