This book is a classic in the history of the Oriental Churches, which are sometimes portrayed as heretical in general church history books, if mentioned at all. Written by a Copt, it portrays the history of the faith of these non-Chalcedonian Churches with first-hand knowledge of their traditions. The author covers Alexandrine Christianity (the Copts and the Ethiopians), the Church of Antioch (Syriac Orthodox), the "Nestorian" Church of the East, the Armenian Church, the St. Thomas Christians of South India, the Maronite Church, as well as the Vanished Churches of Carthage, Pentapolis, and Nubia.

This book is a classic in the history of the Oriental Churches, which are sometimes portrayed as heretical in general church history books, if mentioned at all. Written by a Copt, it portrays the history of the faith of these non-Chalcedonian Churches with first-hand knowledge of their traditions. The author covers Alexandrine Christianity (the Copts and the Ethiopians), the Church of Antioch (Syriac Orthodox), the "Nestorian" Church of the East, the Armenian Church, the St. Thomas Christians of South India, the Maronite Church, as well as the Vanished Churches of Carthage, Pentapolis, and Nubia.