Branch theory

Branch theory is an ecclesiological proposition that the One, Holy, Catholic, and Apostolic Church includes various Christian denominations whether in formal communion or not. Anglican proponents of the theory usually only include the Roman Catholic, Eastern Orthodox and Anglican Communion churches, while others may also include the Oriental Orthodox, Church of the East, Old Catholic and Lutheran churches. The theory is often incorporated in a notion of an invisible Christian Church structure binding them together.

The Oxford Dictionary of the Christian Church defines the theory as:

…the theory that, though the Church may have fallen into schism within itself and its several provinces or groups of provinces be out of communion with each other, each may yet be a branch of the one Church of Christ, provided that it continues to hold the faith of the original undivided Church and to maintain the Apostolic Succession of its bishops. Such, it is contended by many Anglican theologians, is the condition of the Church at the present time, there being now three main branches…

In expounding upon branch theory, theologian states that some view each distinct Christian tradition as contributing something special to the whole of Christendom: "Each church, in its more pronounced form, displays, according to its own native spirit, a particular version of the unique revelation. So, for example, Roman Christianity is characterized by filial love and obedience expressed towards the fatherly authority hypostatized in the first Person of the Trinity: the Church is there to teach and to obey. For the Reformed Churches the vital thing is sacramental reverence for the Word; it is the Church's duty to listen and reform itself. The Orthodox treasure the liberty of the children of God that flowers in liturgical communion, while the Church hymns the love of God for the human race."

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