John of Damascus framed Islam as a heresy, not a new religion

Evidence

The place of his description of Islam should be kept in mind: Islam is the last of one hundred heresies that have plagued the church. John will deploy against Islam the Trinitarian arguments habitually leveled against Jacobites and Nestorians, arguments for free will deployed against the Manicheans, and arguments in defense of crucifixes and icons from the iconoclastic dispute. From John’s perspective, Islam is not a new religion but the last in a long line of deviant Christianities. — John V. Tolan, Saracens, 343

Categorization

• SEED: Article angle: how the ‘Islam as heresy’ frame — a Christian taxonomy that denies Islam independent religious status — is the medieval ancestor of modern tropes that treat Islam as a corruption or derivative of Christianity rather than a religion in its own right.
• XREF: Connects directly to Anidjar’s claim that ‘religion’ is a Western Christian construct applied to Islam; the Damascene taxonomy of Islam as the 100th heresy is the theological genealogy of that denial.