Acts 15:36-39

36 and after certain days, Paul said unto Barnabas, `Having turned back again, we may look after our brethren, in every city in which we have preached the word of the Lord -- how they are.'

37 And Barnabas counseled to take with [them] John called Mark,

38 and Paul was not thinking it good to take him with them who withdrew from them from Pamphylia, and did not go with them to the work;

39 there came, therefore, a sharp contention, so that they were parted from one another, and Barnabas having taken Mark, did sail to Cyprus,