Marcus "polite" was his Latin name and John "Jehovah is Gracious" was his Hebrew name. He has been referred several times in Scripture as John Mark. But many call him "Mark" because of the profusion of "Johns" in the New Testament, much like Judas had the surname "Iscariot" (man of Kerioth) to separate him from another of Jesus' disciples named Judas.Mark appears to have been the cousin of Barnabas, the apostle Paul's traveling companion. Paul mentions this fact when he wrote to the church in Colossae);
10 Aristarchus my fellow prisoner greets you, with Mark the cousin of Barnabas (about whom you received instructions: if he comes to you, welcome him),This would also explain the dispute between Paul and Barnabas during one of Paul's journeys as mentioned in the book of Acts, a dispute so sharp as to cause them to go separate ways;
36 And some days afterward, Paul said to Barnabas, Let us go again and visit our brothers in every city where we have announced the Word of the Lord, how they are doing.
37 And Barnabas determined to take with [them] John, he being called Mark.
38 But Paul thought it well not to take that one with [them], he having withdrawn form them from Pamphylia, and did not go with them to the work.
39 Then there was sharp feeling, as to separate them from each other. And taking Mark, Barnabas sailed to Cyprus.
If Mark was indeed Barnabas' cousin as it appears, this would explain Barnabas' determination to take Mark with him, even though Mark had apparently deserted them at one point during one of Paul's missionary journeys.Mark was present for some of the events that he speaks of in his book. However for the other events told of in his book, scholars believe that Mark received most of his information from the disciple Peter, because Peter had traveled with Jesus from the beginning and was a part of the inner circle of disciples of Jesus.
The book of Mark can be summed up in a single verse:
45 "For even the Son of Man did not come to be served, but to serve, and to give His life a
ransom for many."
Mark's focus is on the service and sacrifice in the life of Jesus. Mark shows Jesus as the
Servant who instantly responds to the will of the Father by preaching, teaching and healing.
He ministers to the needs of others even at the point of death. After His resurrection, He
commissions His followers to continue following in the steps of the perfect Servant.