Christian authors framed new heresies by linking them to earlier discredited errors

Evidence

By this “careful arrangement of [heretics’] ideas as the antithesis of Christianity,” as Brian Stock suggests, Christian authors “attempt to fit a new, troubling experience … into an acceptably conventional framework.” In other words, they tried to make sense of the doctrines or practices that they rejected by connecting them to earlier, discredited errors; Christian authors have the same reflex when confronted with Islam. — John V. Tolan, Saracens, 133