Oriental canon law

Oriental canon law is the law of the 23 Catholic sui juris particular churches of the Eastern Catholic tradition. Oriental canon law includes both the common tradition among all Eastern Catholic Churches, now chiefly contained in the Code of Canons of the Eastern Churches, as well as to the particular law proper to each individual sui juris particular Eastern Catholic Church. Oriental canon law is distinguished from Latin canon law, which developed along a separate line in the remnants of the Western Roman Empire, and is now chiefly codified in the 1983 Code of Canon Law.

A nomocanon is a collection of ecclesiastical law, consisting of the elements from both the civil law and the canon law. Collections of this kind were found only in Eastern law. The Greek Church has two principal nomocanonical collections.

The first nomocanon is the "Nomocanon of John Scholasticus" of the sixth century. He had drawn up (about 550) a purely canonical compilation in 50 titles, and later composed an extract from the Justinian's Novellae Constitutiones in 87 chapters that relate the ecclesiastical matters. To each of the 50 titles was added the texts of the imperial laws on the same subject, with 21 additional chapters, nearly all borrowed from John's 87 chapters.

The second nomocanon dates from the reign of the Byzantine Emperor Heraclius (r. 610 – 641). It was made by fusion of the Collectio tripartita (collection of Justinian's imperial law) and "Canonic syntagma" (ecclesiastical canons). Afterwards, this collection would be known as "Nomocanon in 14 titles". This nomocanon was long held in esteem and passed into the Russian Church, but it was by degrees supplanted by "Nomocanon of Photios" in 883.

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