Orthodoxy

Orthodoxy (from Ancient Greek ὀρθοδοξία (orthodoxía) 'righteous/correct opinion') is adherence to a purported "correct" or otherwise mainstream- or classically accepted creed, especially in religion.

Orthodoxy within Christianity refers to acceptance of the doctrines defined by various creeds and ecumenical councils in antiquity, but different Churches accept different creeds and councils. Such differences of opinion have developed for numerous reasons, including language and cultural barriers. In the Christian world, Eastern Orthodoxy and Oriental Orthodoxy are sometimes referred to simply as "the Orthodox" or "Orthodoxy".

In some English-speaking countries, Jews who adhere to all the contemporarily-applicable commandments legislated in the Written and Oral Torah are often called Orthodox Jews. As this can include many Jews that may not necessarily identify with the term "Orthodox", such as many Masorti Jews, Jewish communities that consider themselves Orthodox are normally united through a diverse, but shared Hashkafic origin from the period of 1818-1821.

Sunni Islam is sometimes referred to as "Orthodox Islam".

The historical Buddha was known to denounce mere attachment to scriptures or dogmatic principles, as it was mentioned in the Kalama Sutta. Moreover, the Theravada school of Buddhism follows strict adherence to the Pāli Canon (tripiṭaka) and the commentaries such as the Visuddhimagga. Hence, the Theravada school came to be considered the most orthodox of all Buddhist schools, as it is known to be highly conservative, especially within the discipline and practice of the Vinaya.^{[citation needed]}

In classical Christian use, the term orthodox refers to the set of doctrines which were believed by the early Christians. A series of 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 of Nicomedia (Arianism). The homoousian doctrine, which defined Jesus as both God and man with the canons of the 431 Council of Ephesus, won out in the Church and was referred to as orthodoxy in most Christian contexts, since this was the viewpoint of previous Christian Church Fathers and was reaffirmed at these councils. (The minority of nontrinitarian Christians object to this terminology.)

Following the 1054 Great Schism, both the Western Catholic Church and the Eastern Orthodox Church continued to consider themselves uniquely orthodox and catholic. Augustine wrote in On True Religion: "Religion is to be sought…only among those who are called Catholic or orthodox Christians, that is, guardians of truth and followers of right." Over time, the Western Church gradually identified with the "Catholic" label, and people of Western Europe gradually associated the "Orthodox" label with the Eastern Church (in some languages the "Catholic" label is not necessarily identified with the Western Church). This was in note of the fact that both Catholic and Orthodox were in use as ecclesiastical adjectives as early as the 2nd and 4th centuries, respectively.

Much earlier, the earliest Oriental Orthodox Churches and Chalcedonian Christianity separated into two after the Council of Chalcedon (AD 451), because of several Christological differences. Since then, Oriental Orthodox Churches have maintained the orthodox designation as a symbol of their theological traditions.