Historically speaking, a singular Christianity is a difficult concept to maintain, given the evidence of the wide-ranging Christian groups that existed in the Ancient World (and even in the Modern World) that believed different things about Jesus of Nazareth to the point where there was little in common or shared amongst some groups. This is clearly the case with the wide range of non-canonical sources and varied Christianities that populated the Ancient Roman world. Discuss four of the many Christian groups that existed in the Ancient World. Who were they? What did they believe? Where did they operate? How long did they last? What writings did they produce if any? Discuss three of these writings and the ideas they express as related by Ehrman. What does this say about the diversity of Christian views in the Ancient World?
https://archive.org/stream/JesusInterrupted-RevealingTheHiddenContradictionsInTheBibleAndWhyWeDontKnowAboutThemBartD.Ehrman/Jesus%20Interrupted%20%E2%80%93%20Revealing%20the%20Hidden%20Contradictions%20in%20the%20Bible%20and%20Why%20We%20Don%E2%80%99t%20Know%20About%20Them%20-%20Bart%20D.%20Ehrman_djvu.txt
Cultures of the West, A History: Vol. I to 1750. 4th Ed. Clifford R. Backman.