Well think about it, Barnabas already parted from Paul. Paul didn't want to go with Mark. So that takes Paul completely off the list. So it was Barnabas and Mark who went.
This is recorded in the book of Acts in the Holy Bible. One day Paul said to Barnabas:<em> “Let’s go back and visit each city where we previously preached the word of the Lord, to see how the new believers are doing” </em>Barnabas agreed and wanted to take along John Mark. However, Paul disagreed strongly, since John Mark had deserted them in Pamphylia and had not continued with them in the labor of preaching the Gospel. Their disagreement was so sharp that they separated. So Barnabas took John Mark with him and sailed for Cyprus.
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