Heretics and Heresies
Heresy, deviation from accepted religious doctrine or practice, was a familiar problem to Christians from the first century through the 17th. In the early days of Christianity, much heresy was accidental. Widely separated groups of Christians, lacking any regular contact with each other, simply developed different interpretations on doctrinal issues. These were commonly settled by periodic meetings of the senior clergy, albeit not without acrimony. Once Christianity became the official religion of, first the Roman empire and then of the Germanic kingdoms founded upon the ruinsof the empire, the majority clergy could call in the civil authorities to force the heretics to mend their ways.
Heresies took many forms. Some derived from legitimate disputes over the interpretation of Scripture, the simple tale told by Matthew, Mark, Luke, John, and the others being heavily worked over under the influence of Greek philosophical ideas to the point where folks could get into arguments about whether the communion wafer should be made with yeast or without it. There was a lot of splitting hairs in this department. For example, it was not considered heretical to translate the Bible from Latin to a vulgar (French, German, English, etc.) language. What was heretical was to then assert that the translation was a valid as the Latin original.
Sometimes a charismatic preacher came would along who taught a revolutionary new version of the faith: One such fellow managed to convince a surprisingly large group of people in Anatolia that the crucifiction had to be reenacted regularly, in effect introuducing human sacrifice to Christianity, an undoubted heresy from any point of view. Islam also had an influence, it's rigid prohibiton against images of any sort found adherents among some Christians in the Eastern Roman Empire, so that for a time several emperors and patriarchs championed the iconoclastic (i.e., "image breaking") movement, a development which became one of the early causes of the split between Roman and Greek Catholicism. Many heretical movements were reflections of social tensions, and many promoted free love, communal property, and absolute equality. Some reflected grassroots dissatisfaction with developments in the Church or became inertwined with nationalist aspirations, such as the Hussite movement.
There were several ways in which the Church could deal with heresies. At the simplest level, it could express its displeasure with the heretical preachers by issuing excommuniations and anathemas, a procedure which was quite effective. In other instances, particularly with those radical thinkers whose primary goal was the reform of abuses within the Church, it could institute a new order, as in the case of the Franciscans, or incorporate the innovations into the Church's doctrine, so that they were no longer heretical at all.. A religious offensive might also be undertaken, strengthening the local clergy with reinforcements in the form of additional priests and monks. And then there was the Inquisition, founded in the later Middle Ages to organize the investigation of heresy. Surprisingly, this was actually a progressive development. Before the creation of the formal Inquistion, the pursuit of heretics was largely in the hands of anyone who was interested in the business, which led to a lot of abuses. The Inquisition, eventually entrusted to the Dominican Order, was instituted to develop a systematic mechanism for sorting out the real heretics from the merely eccentric, such as St. Francis, who might otherwise have suffered from mob violence. Of course the Inquisition grew to be extremely powerful in some countries, and often abusive of that power. It amassed an impressive body count of its own. The number of its victims has been greatly exaggerated. The witch caze which struck the Protestant world in the 17th and 18th centuries probably encompassed more victims than the 30,000 accumulated by the Spanish Inquisition over four centuries. In one case an outbreak of heresy caused a crusade to be preached, since the Albigensian heresy attracted considerable support in high political circles.