Gevurot Meyruach Hakodesh 13:1-2

Now there was in Antioch there among the Moshiachʼs Kehillah nevi'im and morim: Bar-Nabba, and Shim'on called Niger, and Lucius from Cyrene, and Menachem (brought up with Herod the tetrarch) and [Rav] Sha'ul. They were ministering to Adonoi and under a tzom when the Ruach Hakodesh said to them, Set apart for Me Bar-Nabba and Sha'ul for the avodas kodesh ministry to which I have called them.