John of Damascus and Heresy.

This study investigates the understanding of heresy and the heretic according to Saint John of Damascus. For him, a heretic was any Christian who, by wilful choice, departs from the one orthodox tradition by adopting a personal opinion on the common faith which he intends to institute as sole truth. Our research is divided into two parts and aims to apply John of Damascus' understanding of the recurring identity of the Christian heretic and his behaviour. By using historical-theological, interdisciplinary and diachronical approaches, the author demonstrates through two case studies, namely, the Dutch Reformed Churches and Apartheid, and Kimbanguism, that this Church Father, who is the ‘seal of the patristic era,' remains a relevant authority for our comprehension of heresy and the heretic.