Orthodox Christianity

Orthodoxy (from Greek ὀρθοδοξία, orthodoxia – "right opinion") is adherence to correct or accepted creeds, especially in religion. In the Christian sense the term means "conforming to the Christian faith as represented in the creeds of the early Church". The first seven Ecumenical Councils were held between the years of 325 and 787 with the aim of formalizing accepted doctrines.

In some English speaking countries, Jews who adhere to all the traditions and commandments of the Torah are often called Orthodox Jews, though the term "orthodox" historically first described Christian beliefs.

In classical Christian usage, the term orthodox refers to the set of doctrines which were believed by the early Christians. A series of ecumenical councils, also known as the First seven Ecumenical Councils, were held over a period of several centuries to try to formalize these doctrines. The most significant of these early decisions was that between the Homoousian doctrine of Athanasius and Eustathius (which became Trinitarianism) and the Heteroousian doctrine of Arius and Eusebius (called Arianism). The Homoousian doctrine, which defined Jesus as both God and man with the hypostatic union of the 451 Council of Chalcedon, won out in the Church and was referred to as orthodoxy in most Christian contexts, since this was the viewpoint of the majority. (The minority nontrinitarian Christians object to this terminology).

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