Mate. Can you give me evidence to your claim that Mark was written by an eye witness called mark?
According to early sources, Mark was a scribe / interpreter for the Apostle Peter, who was an eyewitness.
Mark Authorship
2. Church Fathers and Mark’s Gospel
Papias (c. 60 to c. 130)
He was the bishop of
Hierapolis.
"Mark having become the interpreter of Peter, wrote down accurately whatsoever he remembered. It was not, however, in exact order that he related the sayings or deeds of Christ. For he neither heard the Lord nor accompanied Him. But afterwards, as I said, he accompanied Peter, who accommodated his instructions to the necessities [of his hearers], but with no intention of giving a regular narrative of the Lord’s sayings. Wherefore Mark made no mistake in thus writing some things as he remembered them. For of one thing he took especial care, not to omit anything he had heard, and not to put anything fictitious into the statements.
Irenaeus (c. 115-c. 202)
He is a rich source of Christian traditions. He was the bishop of Lyons, France. As a boy he knew Polycarp personally. (
Polycarp [c. 69-155] was a disciple of John the Apostle and other apostles, became the bishop of
Smyrna [look under Asia on the map], and was martyred when he was eighty-six years old).
Against Heresies, Book III, Chapter I:
"Matthew also issued a written Gospel among the Hebrews in their own dialect, while Peter and Paul were preaching at Rome, and laying the foundations of the Church. After their departure, Mark, the disciple and interpreter of Peter, did also hand down to us in writing what had been preached by Peter. Luke also, the companion of Paul, recorded in a book the Gospel preached by him. Afterwards, John, the disciple of the Lord, who also had leaned upon His breast, did himself publish a Gospel during his residence at Ephesus in Asia."
Against Heresies, Book III, Chapter X, 5
"Wherefore also Mark, the interpreter and follower of Peter, does thus commence his Gospel narrative: “The beginning of the Gospel of Jesus Christ, the Son of God; as it is written in the prophets, Behold, I send My messenger before Thy face, which shall prepare Thy way."
More in the link above.