“Consider your own call, brothers and sisters: not many of you were wise by human standards, not many were powerful, not many were of noble birth,” says the apostle Paul to the church in Corinth (1Cor 1:26). This tells us much about where the early Christian movement took root. The vast majority of the first Christians were city dwellers; some had money, but few had the kind of social status that would have placed them at the top of the social pyramid.
Contrary to the rural image we have of Jesus and his disciples, the most successful early Christian evangelist was the apostle Paul, who took his message straight to the cities of the Roman Empire. Corinth, Philippi, and Thessalonica, among others, were major urban centers.
Even when we look closely at the birth of the Christian movement after the resurrection of Jesus, the message that Jesus was the Messiah was first preached in a city—Jerusalem. The day of Pentecost occurred in this context (see Acts 2:5, Acts 2:9-11). Cities were preferable evangelizing locations because they had diverse populations. Such diversity allowed a new message to reach a meaningful cross-section of ethnic groups. In short, cities and the roads and shipping paths that connected them were the lifeblood of early Christian expansion.
When we think of the first Christians, we should not think of the super wealthy, nor should we think about those in absolute poverty. They were a more difficult group to define: merchants, artisans, small landowners, and people of similar circumstances formed the core of the first Christian assemblies. People like Philemon, Nympha, Aquila Prisca, and nameless others who hosted early Christian meetings in their homes were the ones who provided the space and the financial resources to keep the movement going. These were people who had resources like private houses. They were able to put aside money on a regular basis to support things like Paul’s ministry and the church in Jerusalem (see, for example, 1Cor 16:1-4). Yes, there were disadvantaged persons involved in the early church as well, as we know from the apostle Paul’s letter to Philemon in the New Testament, which discusses the situation of Philemon’s slave, Onesimus.
The customary practice of Christian conversion, at least among Paul’s churches, appears to have started with the apostle’s arrival in the city. He would then take up an artisan’s job that would have put him in contact with the types of people he was targeting. After convincing a core of individuals of the truth of his message, he would organize a house-church that would meet on a regular basis. These people would continue to share the message and participate in Paul’s ministry through financial gifts and the sending and receiving of letters.
People converted to Christianity for many reasons, and scholars have proposed many theories to account for Christianity’s spread. One thing is certain: those who joined the Christian movement believed they had experienced the risen Christ.