Editing Gnosticism (section)

===Orthodoxy and heresy===
{{See also|Diversity in early Christian theology}}
The Christian [[Heresiology|heresiologists]], most notably [[Irenaeus]], regarded Gnosticism as a Christian heresy. Modern scholarship notes that early Christianity was diverse, and Christian orthodoxy only settled in the 4th{{nbsp}}century, when the Roman Empire declined and Gnosticism lost its influence.{{sfn|Pagels|1979}}{{sfn|Magris|2005|p=3519}}{{sfn|Perkins|2005|p=3529}}{{sfn|Dillon|2016|p=36}} Gnostics and proto-orthodox Christians shared some terminology. Initially, they were hard to distinguish from each other.{{sfn|Perkins|2005|pp=3529–3530}}

According to Walter Bauer, "heresies" may well have been the original form of Christianity in many regions.{{sfn|Bauer|1979}} This theme was further developed by Elaine Pagels,{{sfn|McVey|1981}} who argues that "the proto-orthodox church found itself in debates with Gnostic Christians that helped them to stabilize their own beliefs."{{sfn|Dillon|2016|p=36}} According to Gilles Quispel, Catholicism arose in response to Gnosticism, establishing safeguards in the form of the [[Episcopal polity|monarchic episcopate]], the [[creed]], and the [[Christian biblical canons|canon]] of holy books.{{sfn|Quispel|2004|p=9}} 
On the other hand, [[Larry Hurtado]] argues that [[proto-orthodox Christianity]] was rooted into [[Christianity in the 1st century|first-century Christianity]]:
<blockquote>...to a remarkable extent early-second-century protoorthodox devotion to Jesus represents a concern to preserve, respect, promote, and develop what were by then becoming traditional expressions of belief and reverence, and that had originated in earlier years of the Christian movement.  That is, proto-orthodox faith tended to affirm and develop devotional and confessional tradition [...] Arland Hultgren<ref>''The rise of normative Christianity'', Minneapolis: Fortress Press, 1994.</ref> has shown that the roots of this appreciation of traditions of faith actually go back deeply and widely into first-century Christianity.{{sfn|Hurtado|2005|p=495}}</blockquote>