Μάρκος μαθητὴς καὶ ἑρμηνευτὴς Πέτρου, καθὼς τοῦ Πέτρου ἐξηγουμένου ἀκήκοε, παρακληθεὶς ἐν τῇ Ῥώμῃ παρὰ τῶν ἀδελφῶν, βραχὺ συνέταξεν Εὐαγγέλιον, ᾧπερ ἐντυχὼν Πέτρος ἐδοκίμασε, καὶ τῇ Ἐκκλησία ἀναγνωσθησόμενον αὐθεντίσας ἐξέδωκε, καθὰ 844 συνεγράψατο Κλήμης ἐν τῷ ἕκτῳ τῶν Υποτυπώσεων λόγῳ, καὶ Παπίας Ἱεραπολίτης Ἐπίσκοπος. Μέμνηται τούτου τοῦ Μάρκου καὶ Πέτρος ἐν τῇ πρώτῃ Ἐπιστολῇ, ἐπ' ὀνόματι Βαβυλῶνος εἰκονικῶς Ῥώμην σημαίνων. Ἀσπάζεται ὑμᾶς, φησὶν, ἡ ἐν Βαβυλῶνι σὺν τῇ ἐκλεκτῇ, καὶ Μάρκος ὁ ἐμὸς υἱὸς. Παραλαβὼν τοιγαροῦν τὸ Εὐαγγέλιον (he took therefore the gospel), ὅπερ αὐτὸς συνέταξε (which he himself wrote), καταλαμβάνει τὴν Αἴγυπτον, καὶ πρῶτος ἐν Ἀλεξανδρείᾳ Ἰησοῦν Χριστὸν κηρύττων, κατεστήσατο ἐκκλησίαν, τοσαύτῃ παιδεύσει καὶ βίου καρτερίᾳ διέπρεψεν, ὥστε πάντας τοὺς ἀκολουθοῦντας τῷ Χριστῶ ἕψεσθαι τῇ τούτου διαγωγῇ. Ὅθεν καὶ Φίλων ὁ τῶν Ἰουδαίων ἐλλογιμώτατος, ὁρῷν ἐν Ἀλεξανδρείᾳ πρώτην ἐκκλησίαν ἔτι Ἰουδαΐζουσαν, ὡσανεὶ εἰς ἔπαινον τοῦ οἰκείου ἔθνους βίβλον περὶ τῆς τούτων διαγωγῆς συνεγράψατο. Καὶ ὥσπερ Λουκᾶς διηγεῖται τοὺς ἐν Ἰεροσολύμοις πιστεύσταντας πάντα ἐσχηκέναι κοινὰ, οὕτως κᾀκεῖνος ὅπερ ἐν Ἀλεξανδρείᾳ ἐπὶ Μάρκου τοῦ διδασκάλου ἐώρα γινόμενον, τῇ μνήμῃ παρέδωκε. Τελευτήσας δὲ τῷ ὀγδόῳ τοῦ Νέρωνος ἔτει, ἀπετέθη ἐν Ἀλεξανδρείᾳ, διαδεξαμένου αὐτὸν Ἀνανίου.
Mark the disciple and interpreter of Peter wrote a short gospel (βραχὺ συνέταξεν Εὐαγγέλιον) at the request of the brethren at Rome embodying what he had heard Peter tell. When Peter had heard this, he approved it and published it to the churches to be read by his authority as Clemens in the sixth book of his Hypotyposes and Papias, bishop of Hierapolis, record. Peter also mentions this Mark in his first epistle, figuratively indicating Rome under the name of Babylon She who is in Babylon elect together with you salutes you and so does Mark my son. So, taking the gospel which he himself composed, he went to Egypt and first preaching Christ at Alexandria he formed a church so admirable in doctrine and continence of living that he constrained all followers of Christ to his example.
Jerome's rewriting of Eusebius seems to imply that in addition to the gospel which he wrote at Rome a doctrine of continence was added to Christian teachings at Alexandria. There is no specific reference to the gospel at Alexandria itself being 'longer' per se. Nevertheless something of the notion in To Theodore is present - namely that where as the gospel in Rome was all about Peter, the gospel or doctrine at Alexandria was all about Mark (cf. Constituit ecclesiam tantâ doctrinâ et vitæ continentiâ ut omnes sectatores Christi ad exemplum sui cogeret--He so adorned, by his doctrine and his life, the church which he founded, that his example influenced all the followers of Christ.).Eusebius Church History 2.15 And thus when the divine word had made its home among them, the power of Simon was quenched and immediately destroyed, together with the man himself. And so greatly did the splendor of piety illumine the minds of Peter's hearers that they were not satisfied with hearing once only, and were not content with the unwritten teaching of the divine Gospel, but with all sorts of entreaties they besought Mark, a follower of Peter, and the one whose Gospel is extant, that he would leave them a written monument of the doctrine which had been orally communicated to them. Nor did they cease until they had prevailed with the man, and had thus become the occasion of the written Gospel which bears the name of Mark.
2. And they say that Peter — when he had learned, through a revelation of the Spirit, of that which had been done — was pleased with the zeal of the men, and that the work obtained the sanction of his authority for the purpose of being used in the churches. Clement in the eighth book of his Hypotyposes gives this account, and with him agrees the bishop of Hierapolis named Papias. And Peter makes mention of Mark in his first epistle which they say that he wrote in Rome itself, as is indicated by him, when he calls the city, by a figure, Babylon, as he does in the following words: The church that is at Babylon, elected together with you, salutes you; and so does Marcus my son. 1 Peter 5:13
16. 1. And they say that this Mark was the first that was sent to Egypt, and that he proclaimed the Gospel which he had written, and first established churches in Alexandria.
2. And the multitude of believers, both men and women, that were collected there at the very outset, and lived lives of the most philosophical and excessive asceticism, was so great, that Philo thought it worth while to describe their pursuits, their meetings, their entertainments, and their whole manner of life.
Clement for his part has the same Rome = Peter, Alexandria = Mark formula:
Jerome has reshaped Eusebius's original testimony with knowledge or hints of Secret Mark.As for Mark, then, during Peter's stay in Rome he wrote an account of the Lord's doings, not, however, declaring all of them, nor yet hinting at the secret ones, but selecting what he thought most useful for increasing the faith of those who were being instructed. But when Peter died a martyr, Mark came over to Alexandria, bringing both his own notes and those of Peter, from which he transferred to his former book the things suitable to whatever makes for progress toward knowledge. Thus he composed a more spiritual Gospel for the use of those who were being perfected.