The fasting and praying was done by the office bearers of the church in Antioch. It is possible that the church community as a whole is in view,1,2 though the context implies that reference is made only to the office bearers. Most likely they would have prayed for the Lord to give Saul and Barnabas wisdom, that he would guide them in their journey, grant them courage to speak boldly and look after them.3
3 Then after fasting and praying they laid their hands on them and sent them off.