Now on to chapter 3, which is about Paul's first missionary journey. See Acts 13.
So Paul was at Antioch just a year or so after the famine, when God called Barnabas and him to go on a missionary journey. The first of several for Paul.
It was a prophetic word. It was early on a Sunday morning, just before dawn. A group of about thirty people were gathered to pray and worship at a certain point along the Orontes River, just outside the city walls of Antioch of Syria. After singing a psalm, Agabas was filled with the Holy Spirit and said, "God is setting aside Saul and Barnabas to take the good news to Cyprus, to Barnabas' own land." 
Barnabas was born on the island of Cyprus. However, like Paul, he also had family in Jerusalem. In fact, Jesus ate his last supper in an upper room in his sister Mary's house. The leaders of the Jerusalem church assembled in that unusually large room for worship and a love feast each week. It was the house where Peter stayed when he was in Jerusalem. This Mary was one of those who had followed Jesus to the cross and had been there when they discovered the empty tomb. 
Mary had several sons, the youngest of which was named John Mark. Mark was an enthusiastic and curious young man, not to mention somewhat impulsive. The night of Jesus' arrest, he didn't even take time to fully dress, but ran out with only his outer garment on. When one of the high priest's guards noticed him and grabbed his cloak, he ditched it and ran away naked. 
Barnabas thought the journey might help him mature. Mark was excited because he admired his uncle Barnabas, who was in charge of the mission. And he had never been to Cyprus before to visit that side of the family.
Paul--who was still going by "Saul" at that time--was not particularly impressed with Mark. What Paul needed was someone to carry stuff and run errands. But Mark came from a wealthy family that even had servants in their house. Let's just say that there weren't any callouses on his hands.
The tension between Paul and Mark seemed to grow every day. Mark did not do enough for Paul's liking. Mark did not have any common sense, at least as far as Paul was concerned. Half the tasks he did, he did wrongly.
Meanwhile, Mark was increasingly annoyed at how Paul seemed to take charge all the time. Wasn't his uncle Barnabas the leader of this mission? Why did Paul end up doing most of the talking?
And Mark was really annoyed at how chummy Paul was with the Roman governor Sergius Paulus. Their mission wasn't to spread the good news to Gentiles but to Jews, Mark thought at the time. And Paul always seemed to rub other Jews the wrong way. If he would just let Barnabas talk, Mark thought, more Jews would believe. In fact, the only reason Paul met Sergius Paulus in the first place was because Paul got thrown in jail at the accusation of provoking a riot in the local synagogue...
 We do not know which prophet had this word, nor do we know where all the assemblies of Antioch met. I pictured them meeting next to the river based on where some met at Philippi. See Acts 13 and 16.
 It seems reasonable to connect the upper room, Mary, and John Mark together, since Peter goes there in Acts 12. However, we do not know if this Mary is the wife of Clopas and mother of James and Joseph mentioned in the Gospels.
 It's an old suggestion that this young man was Mark. Of course we do not know for sure. In fact, the Gospel of Mark itself is technically anonymous.