Acts 15:36-39

And some days after Paul said unto Barnabas, Let us go again and visit our brethren in every city where we have preached the word of the Lord, and see how they do. And Barnabas determined to take with them John, whose surname was Mark. But Paul thought not good to take him with them, who departed from them from Pamphylia, and went not with them to the work. And the contention was so sharp between them, that they departed asunder one from the other: and so Barnabas took Mark, and sailed unto Cyprus