The early sources. The New Testament ; The Apostolic Fathers ; Other sources
Anonymous canonical works. Works dependent on the Didache ; Works dependent on the Apostolic tradition of Hippolytus
Authors of the fourth and fifth centuries. Ephraim the Syrian ; Athanasius the Great ; Basil the Great ; Gregory of Nazianzus ; John Chrysostom ; Ambrose of Milan ; Other patristic testimonies
The councils of the fourth and fifth centuries. The Council of Ancyra ; The Council of Neocaesarea ; The First Ecumenical Council (Nicaea) ; The Council of Sardica ; The Council of Laodicea ; The Council of Carthage ; The Fourth Ecumenical Council (Chalcedon)
The marriage of the clergy and relevant legislation. The Christian view of celibacy ; The influence of monasticism ; The Council of Elvira ; The Council of Ancyra ; The Council of Neocaesarea ; The First Ecumenical Council (Nicaea) ; The Council of Gangra ; Later legislation
Prerequisites for entry into the clergy in the first five centuries on the basis of the sources reviewed. Physical criteria ; Spiritual criteria.
