After the ascension of Jesus in 33 AD 120 of His disciples met for prayer in Jerusalem for 10 days. In 313, Constantine, ensured religious tolerance for Christians. It has been supposed that sometime during this period Constantine ordered mass conversions for his troops and followers and that resulted in the dramatic increase in Christianity.
Rodney Stark in “The Rise of Christianity” gives 5 other more compelling reasons for the increase to 56.5% of world population by 350 AD in a hostile and non-receptive environment.
One, “Central doctrines of Christianity prompted and sustained attractive, liberating, and effective social relations and organizations.” These included “For God so loved the world”, “love one another”, “love your enemies”, “a merciful God expects His followers to care for and be merciful to others”, “salvation is by faith alone”, “eternal life after death in heaven with God”, etc. These doctrines fulfilled in lives resulted in liberating relations between the sexes, family, classes of people from slaves to bosses, differences in ethnicity, etc. This favored Christians in population growth. [There has been a dramatic decline in % of people practicing Christianity in the western world since 1945. In the rest of the world Christianity has been increasing, especially in China and Africa.]
Two, the Christians refused to participate in pagan customs such as murdering unwanted babies–particularly girls, abortion, homosexuality, promiscuous behavior, very low views of marriage, worship of many false gods, emperor worship, etc. There were many more men than women pagans as a result. The opposite behavior by Christians and increased fertility dramatically increased the growth of Christians compared to pagans. [All of these pagan customs are broadly accepted in the western world today.]
Three, during this time there was no antibiotics, effective medicines, or even awareness of how disease spread. In the cities for other than the ruling class there was no sanitation, etc. The average person lived in filth beyond comparison. As a result there was various local plagues and at least two wide spread plagues during these years resulting in the death of maybe 1/3 of the population for each plague. The average life span was less than 30 years. The pagans were afraid and deserted their sick and discarded them to die unburied. The Christians fearless of death, cared for their sick and buried their dead and the pagans dead. This care resulted in wide differences in deaths in favor of Christians. [The life span in the U. S. has declined recently. Here is a current day example of Christians caring for Ebola victims– Facing Darkness ]
Four, natural and social disasters, in Antioch in 600 years as an example: the city was taken by unfriendly forces eleven times, and was plundered on five of these occasions; it was burned entirely in large part four times, severe fires were frequent, there were six major periods of rioting resulting in substantial damage and deaths. Antioch suffered literally hundreds of significant earthquakes during the 6 centuries, but eight destroyed virtually everything. At least three killer epidemics struck the city with deaths running above 25 % each. Five really serious famines occurred. That was 41 catastrophes or one every 15 years. [Major natural and social disasters,including riots are occurring in the U. S. today]
Five, all of these problems resulted in low growth rates in the cities that did not sustain the population. Ethnic chaos was created by people moving from rural areas and other regions of different ethnicities with different languages and customs to maintain the population. Christians were more welcoming, encouraging, patient, willing to assimilate people who were different and eventually converting many. [This is occurring all over the western world today. More so in Europe, Japan, India, and China, with virtually every country below the sustainable rate of 2.1 births for each women. This has been one of the reasons for unlimited immigration in the U.S. and Europe.]
Stark argues that Christianity’s superior capacity for meeting all these problems soon became evident and played a major role in its dramatic growth of 40% per decade from 40 to 350 AD. He estimates that because of these reasons in 350 AD there were 33.9 million Christians or 56.5% of estimated population of 60 million. [Page 6-7 Stark] [To me this gives tremendous encouragement to disciples today who are willing to follow Jesus in His power and grace: “Then Jesus said to His disciples, “If anyone wishes to come after Me, he must deny himself, and take up his cross and follow Me.”” Matthew 16:24]
Henry Luke 4/2/2017