Earliest Catacomb representation of Jesus, Peter, Paul, and Andrew. in Rome
1 The beginning of the good news about Jesus the Messiah, the Son of God, 2 as it is written in Isaiah the prophet:
“I will send my messenger ahead of you,
who will prepare your way”—
3 “a voice of one calling in the wilderness,
‘Prepare the way for the Lord,
make straight paths for him.’”
Who was Mark? This is difficult to say. Timothy was Paul's Spiritual Son. Peter claims Mark.
1 Peter 5:13
She who is in Babylon, chosen together with you, sends you her greetings, and so does my son Mark.
Paul loved Mark.
2 Timothy 4:11
Only Luke is with me. Get Mark and bring him with you, because he is helpful to me in my ministry.
Paul argued with Barnabas over Mark
My fellow prisoner Aristarchus sends you his greetings, as does Mark, the cousin of Barnabas.
Then Peter came to himself and said, “Now I know without a doubt that the Lord has sent his angel and rescued me from Herod’s clutches and from everything the Jewish people were hoping would happen.”
12 When this had dawned on him, he went to the house of Mary the mother of John, also called Mark, where many people had gathered and were praying. 13 Peter knocked at the outer entrance, and a servant named Rhoda came to answer the door.
Perhaps, due to early Church wranglings - Mark was Peter's literal son. (If Mary was [historically, wealthy] Peter's wife and he was dazed. In the Roman Empire, women held on to Roman Inheritance.)
And Barnabas's cousin.
And Paul's co-minister.
Then Mark would represent - Christian forgiveness.
And the true believer's humility to exalt Jesus.
1 Corinthians 12:11-14
All these are the work of one and the same Spirit, and he distributes them to each one, just as he determines.
Just as a body, though one, has many parts, but all its many parts form one body, so it is with Christ. 13 For we were all baptized by one Spirit so as to form one body—whether Jews or Gentiles, slave or free—and we were all given the one Spirit to drink. 14 Even so the body is not made up of one part but of many.
"The most important one," answered Jesus, "is this: 'Hear, O Israel: The Lord our God, the Lord is one."
St Mark wrote his Gospel for busy people of the Roman Empire. Historical references - a concise record a busy person could refer to, the references to the Miracles of Jesus most often spoken of. Only 16 chapters. The words and deeds of the Savior which reveal His divine Power. The account of Jesus people asked about the most, explained by Mark's closeness to the disciples. The obvious goal being to experience of the living Jesus Christ.
The proclamation of Jesus in Mark 1:14 and the following verses, for example, mixes the terms Jesus would have used as a 1st century Jew ("kingdom of God") and those of the early church ("believe", "gospel"). Counter belief against those who saw Jesus in a Greek way, as wonder-worker (the Greek term is "divine man"). Many ancient historians record the Gospel of Mark is a concise record of St Peter's preaching. Mark saw the suffering of the messiah as essential, so that the Son of God title (the Hellenistic "divine man") had to be corrected and amplified with the "Son of Man" title, which conveyed Christ's suffering unto victory over death.
He said to them, "Go into all the world and preach the gospel to all creation."
This we know Mark did. Knowing more clearly of his work for Jesus than his parentage. We know Mark was the first Bishop in Africa and died in Alexandria in 68 A.D.
Mark's concern in presenting the life of Jesus was that the most widely spoken of miracles in the 1st century A.D. were recording expressing Jesus as the Messiah bringing us Good News of God's unity over all of creation. Mark brought Jesus to the millenniums.