I never really thought about this before, but who were Mark and Luke since they weren’t one of the disciples?
Thank you for your question.
Mark’s full name was John Mark (Acts 12:12). His Christian life was influenced by his mother, Mary, as well as by his cousin, Barnabas, who took him with Paul on Paul’s first missionary journey (Acts 13:5). Halfway through this journey, Mark returned home (Acts 13:13). His departure caused Paul to not want to take him on his second missionary trip, and this caused Paul and Barnabas to part company (Acts 15:39). Instead, Barnabas set sail with Mark for the island of Cyprus. In later years however, Paul also commended Mark’s efforts in the ministry (2 Timothy 4:11).
Luke was a doctor, and one of Paul’s closest companions and fellow laborers (Colossians 4:14, Philemon 24, and 2 Timothy 4:11). Luke is also widely believed to be the author of the book of Acts as well.
I hope this helps.