Acts
King James Version (KJV)

“As they ministered to the Lord, and fasted, the Holy Ghost said, Separate me Barnabas and Saul for the work whereunto I have called them.”
King James Version (KJV)
13:2 Separate me Barnabas and Saul for the work to which I have called them - This was not ordaining them. St. Paul was ordained long before, and that not of men, neither by man: it was only inducting him to the province for which our Lord had appointed him from the beginning, and which was now revealed to the prophets and teachers. In consequence of this they fasted, prayed, and laid their hands on them, a rite which was used not in ordination only, but in blessing, and on many other occasions.
Ac 13:2 As they ministered. These men worshiped before the Lord, fasting, and no doubt asking for guidance in the extension of Christianity. The Holy Ghost said. By an inspiration given to some one of these prophets. "God has spoken at sundry times and in divers manners unto the fathers by the one of these prophets" (Heb 1:1). Compare Ac 20:23. Separate me Barnabas and Saul. Both had been tried and shown to be worthy. They are now, by Divine direction, to be formally consecrated to the work of preaching the gospel to the Gentiles. From this time Antioch is the great missionary center. For the work whereunto I have called them. God called; men separated, or formally set apart.