Acts 15:36-38

³⁶And some days after, Paul said to 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.

³⁷And Barnabas determined to take with them John, whose surname was Mark.

³⁸But Paul thought not good to take him with them, who departed from them from Pamphylia, and went not with them to the work.