How Did Christianity Spread?
The earliest Christians did not have church buildings. They typically met in homes. (The first actual church building so far found is at Dura Europos on the Euphrates, dating about 231.) They did not have public ceremonies that would introduce them to the public, and they had no access to the mass media of their day. So, how can we account for their steady and diverse expansion over the first three centuries?
After the Apostle Paul, we do not run across many "big names" as missionaries in the first few hundred years of Christian history. Instead, the faith spread through a multitude of humble, ordinary believers whose names have been long forgotten.
Early Christianity was primarily an urban faith, establishing itself in the city centers of the Roman Empire. Most of the people lived close together in crowded tenements. There were few secrets in such a setting. The faith spread a…