At first glance, it seems as though Antioch marks just another step in the process of the Jesus movement becoming more open, but in fact, Antioch marks a paradigm shift: a complete break with the past. In this short passage we see two very significant things happening.
The first is that the Greek believers who started telling other Greeks about Jesus didn’t tell them about Jesus the Messiah, they spoke about the Lord Jesus. This may only seem like a small thing, but it has huge consequences. Messiah was a Jewish term and would mean almost nothing to Greeks, so the disciples found a Greek term: Lord, to use in its place. The miracle at Pentecost told the disciples that any language could be used for the Gospel and now these Greek believers are putting that lesson into practice. In order to explain the message of Jesus they dropped the sacred term Messiah and used the easily understandable word ‘Lord’ instead. They taught about Jesus according to the context in which they found themselves. Because the believers had basically lived in a Jewish context up until now, they had never had to do anything like this before. But this little group of Greek disciples were now starting to use and develop the principles of cross-cultural mission.
There were a couple of unintended consequences of the use of the term Lord. The first is that people started to treat the word Messiah, or Christ in its Greek form as part of Jesus name. Jesus Christ is Lord, really means that Jesus the Messiah is Lord, but we think of Christ as being Jesus family name as in John Smith is my friend. The other consequence is that the confession, Jesus Christ is Lord eventually brought the believers into conflict with the Roman Empire. The Romans proclaimed that Caesar, the Emperor was God and they swore allegiance to him by saying that Caesar is Lord. The disciples refused to say that, for them there was only one Lord: Jesus Christ. Many of them suffered for this simple confession of faith.
Alongside the use of the word Lord, the other significant thing that happened at Antioch was that this is where the disciples were first called Christians. In all probability this was an insult. People who had been crucified were considered the lowest of the low and to name the disciples after a man who had been crucified as a criminal was to brand them with a pretty unpleasant name. But the disciples took it as a badge of honour, and from now on the Jesus movement has a name: Christianity. They were still not completely separated from Judaism, but it was now clear that this was a distinct group, not just a slightly strange Jewish sect.
It is no surprise that the Christians gained a distinct identity in the same place that they got to grips with reaching out to others in mission. As long as they stayed within their Jewish cocoon, they were not able to become the people that God intended them to be. But in Antioch, they broke free of that cocoon, reaching out to their Gentile neighbours with the Good News of Jesus and in the process, they became the Christian Church. It was mission that gave them their sense of separate identity from their Jewish roots. The Church was born in Antioch, not Jerusalem!