Before we begin to discuss the portrayal of various “heretics” in ancient Christian literature, we need to clarify the language of “orthodoxy” and “heresy.” From a sociological perspective, this language is about creating social boundaries between insiders and outsiders around a certain set of beliefs and practices. From a theological perspective, for those who belong to a community of faith, it is about upholding truth and weeding out falsehood.
Robert M. Royalty’s piece “Heresy in Earliest Christianity” for the website Bible and Interpretation discusses the origins of the terminology we use. Basically, although different New Testament writers polemicized against teachings or practices that they regarded as false, the Greek word haeresis itself was a neutral term denoting an option or choice, like a school of thought advocated by an individual or group that one might choose to embrace. Eventually, it took on the more pejorative connotations of Christian sects that deviated from the normative “rule of faith” handed down from the Apostles (“sent ones”) of Jesus to the bishops or overseers guarding the “universal” (Catholic) church. The church fathers pictured different heretical philosophical schools – Simonians, Nicolaitans, Cerinthians, Basilideans, Carpocratians, Marcionites, Valentinians, and so on – headed by a particular false teacher (Simon, Nicolas, Cerinthus, Basilides, Carpocrates, Marcion, Valentinus). The Jewish Christian sect of the Ebionites even gets the fictional founder Ebion. However, while the professional heresiologists who saw it as their job to expose and overthrow false teachings drew clear boundaries between groups, the reality on the ground may have been far messier with diverse lay Christians continuing to meet together and influence one another without always recognizing where their theological beliefs and practices differed subtly or significantly.