The Orthodox Faith serves as a quintessential representation of the Early Greek Fathers teachings. Written just before the final truly Ecumenical Councils of 787, this work stands as the last Eastern theological contribution wholeheartedly embraced by the West. As an ecumenical touchstone, it continues to hold authority in Eastern Orthodoxy, Roman Catholicism (notably through Peter Lombards Sentences), and in Reformation Churches eager to shed late medieval additions and return to the foundational principles of Creedal Christianity. (Summary by Jonathan Lange)