Ecclesiastical hierarchy

In Christian theology, Ecclesiology is the study of the Christian Church, the origins of Christianity, its relationship to Jesus, its role in salvation, its polity, its discipline, its destiny, and its leadership. Since different ecclesiologies give shape to very different institutions or denominations, there are many subfields such as Catholic ecclesiology, Protestant ecclesiology, and ecumenical ecclesiology.

The word ecclesiology was defined in the 19th century as the science of the building and decoration of church buildings and at least one publication still uses the word in this sense.

The roots of the word ecclesiology come from the Greek ἐκκλησίᾱ, ekklēsiā (Latin ) meaning ", " and -λογία, -logia, meaning "words", "knowledge", or "logic", a combining term used in the names of sciences or bodies of knowledge.

The similar word ecclesialogy first appeared in the quarterly journal The British Critic in 1837, in an article written by an anonymous contributor who defined it thus:

We mean, then, by Ecclesialogy, a science which may treat of the proper construction and operations of the Church, or Communion, or Society of Christians; and which may regard men as they are members of that society, whether members of the Christian Church in the widest acceptation of the term, or members of some branch or communion of that Church, located in some separate kingdom, and governed according to its internal forms of constitution and discipline.

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