What does Acts 12:12 mean?
An angel has just rescued Peter from prison, moments before Herod Agrippa I planned on having him escorted to his execution (Acts 12:6–11). Peter must go into hiding, but before he does, he wants the church to know he's okay. He goes to the home of Mary, the mother of John Mark. The believers there are meeting to pray, very likely for Peter.Luke (Luke 1:1–4; Acts 1:1) doesn't identify Mary out of some misogynistic impulse—as if she's only important because of her son. The fact is besides the mother of Jesus, Mary Magdalene, and Mary of Bethany, the New Testament mentions three other women named Mary. Given that it's such a common name, Luke's audience would need clarification. Indeed, John Mark is identified by his mother. Tradition says Mary owned the upper room where Jesus held the Last Supper and the disciples had their headquarters (Acts 2:1). The fact that Peter knew to go to her upon his release indicates her importance in the Jerusalem church.
The New Testament identifies several men named "John," as well. The one noted here is not John the Baptist, of course, whose mother is Elizabeth. And it is not the son of Zebedee and brother of James; his mother's name is probably named Salome (Mark 1:19; 15:40). This is Barnabas' cousin (Colossians 4:10).
"John" is Mary's son's Hebrew name while "Mark" is his Roman name. We don't know about his father—if he was a Gentile—but by the time of Luke's writing he is a respected member of the church. Shortly, he will set off with Barnabas and Paul to share Jesus' story on the island of Cyprus and up into modern-day Asia Minor. But immediately after they leave the island and reach the mainland he will return to Jerusalem, earning Paul's censure (Acts 12:25—13:13). When Paul and Barnabas coordinate their second journey, Barnabas will insist on giving him another chance while Paul will refuse. In response, Barnabas will take Mark back to Cyprus while Paul takes Silas to Asia Minor (Acts 15:36–41).
Later, Mark will write the first Gospel, likely with the help of Peter. And Paul will tell Timothy, "Get Mark and bring him with you, for he is very useful to me for ministry" (2 Timothy 4:11). Some scholars conjecture that Mark is the youth who loses his sheet while he runs from Jesus' arrest (Mark 14:51–52).
