One of the first things that comes up in a discussion of early Christianity is the issue of orthodoxy and heresy. What is orthodoxy? What is heresy? Who decides?
Walter Bauer and Barth Ehrman have set forth a reconstruction of early Christian history in which Christianity was made up of incredible diversity. There were numerous vibrant groups of Christians with divergent views about God, Christ, the church, salvation, etc. These groups existed side by side, often in debate, but none of these groups having the theological upper hand. Only after the rise of Constantine in the 4th century and the subsequent squelching of all but one strand of Christian faith was there an imposed unity of orthodoxy.
Contra this opinion are writers such as H.E.W. Turner, Andreas Kostenberger, and Michael Kruger (I have read Turner, and look forward to reading Kostenberger and Kruger's The Heresy of Orthodoxy) who argue that while there was some diversity in pre-Constantinian Christianity, there was more or less a norm of Christian belief which could then be used as a standard to judge heretical elements.
What we know for sure is this: pre-Constantine we do have evidence of diversity in Christianity. This cannot be denied since we have the literature from groups with divergent beliefs. What we do not know is the extent to which these groups had a following. Besides what could be labeled as proto-orthodox writings (that is, those in line with what was later to be deemed orthodox), which had a wide distribution and following, we do not know to what extent other writings were influential. For example, the gnostic writings found at Nag Hamadi, while fascinating, may not have had much influence at all on the vast majority of Christians.
Here's what D.A. Carson has to say about this view of heresy and orthodoxy in the pre-Constantinian period. (from blurb on the back of Kostenberger and Kruger's book The Heresy of Orthodoxy).
“In the beginning was Diversity. And the Diversity was with God, and the Diversity was God. Without Diversity was nothing made that was made. And it came to pass that nasty old ‘orthodox’ people narrowed down diversity and finally squeezed it out, dismissing it as heresy. But in the fullness of time (which is of course our time), Diversity rose up and smote orthodoxy hip and thigh. Now, praise be, the only heresy is orthodoxy. As widely and as unthinkingly accepted as this reconstruction is, it is historical nonsense: the emperor has no clothes. I am grateful to Andreas Köstenberger and Michael Kruger for patiently, carefully, and politely exposing this shameful nakedness for what it is.”
—D. A. Carson, Research Professor of New Testament, Trinity Evangelical Divinity School (HT Rod Decker and NT Resources Blog)So, which reconstruction of early Christian history do you find most persuasive?