Church history is the story of the important events in the existence of a visible, organized body of persons professing faith in Christ as the divine Saviour. Which body, some would add, possesses a direct succession from the apostles under and through a continuous episcopate, or, as others would add, under and through the Roman Pontiffs.

It is the story of how Christians have believed within themselves, which is theology, of how they have behaved before one another and the world, which is morality, how they have worshipped God, which constitutes religious rites and observances, how they have governed their brethren, which is ecclesiastical discipline, how they have multiplied their friends, which is missions, and how they have received benefit or injury as a body from the world outside, which constitutes the Church's secular relationship.