Early Christian tradition associates the Second Gospel with Mark and connects his account particularly with the apostolic preaching of
Peter. The New Testament knows John Mark as the son of Mary of Jerusalem and cousin of
Barnabas. He accompanied Barnabas and
Saul but withdrew at Perga, later causing disagreement between Barnabas and
Paul. Subsequent letters show that Mark regained Paul's trust and became useful for ministry. First Peter refers to 'Mark, my son,' supporting a close relationship with Peter. These data fit the ancient tradition connecting Mark with Peter's testimony, though the Gospel itself remains formally anonymous and does not identify John Mark as its author.