The Greek word denotes, primarily, a straight rod; hence a rule or standard, by a reference to which the rectitude of opinions or actions may be decided. In the latter sense it is used in Galatians 6:16 Philippians 3:16. In the same sense it was used by the Greek fathers. As the standard to which they sought to appeal on all questions was the will of God contained in the Scriptures of the Old and New Testaments, they came naturally to apply this term to the collective body of those writings, and to speak of them as the canon or rule. Canon is also equivalent to a list of catalogue, in which are inserted those books which contain the inspired rule of faith.

In order to establish the canon of Scripture, it must be shown that all the books are of divine authority; that they are entire and incorrupt; that it is complete without addition from any foreign source; and that the whole of the books for which divine authority can be proved are included. See BIBLE.

The Old Testament Canon is witnessed to by the New Testament writers. Their evidence is conclusive. The quotations in the New from the Old are very numerous, and the references are much more numerous. These quotations and references by our Lord and the apostles most clearly imply the existence at that time of a well-known and publicly acknowledged collection of Hebrew writings under the designation of "The Scriptures;" "The Law and the Prophets and the Psalms;" "Moses and the Prophets," etc. The appeals to these books, moreover, show that they were regarded as of divine authority, finally deciding all questions of which they treat; and that the whole collection so recognized consisted only of the thirty-nine books which we now posses. Thus they endorse as genuine and authentic the canon of the Jewish Scriptures. The Septuagint Version (q.v.) also contained every book we now have in the Old Testament Scriptures. As to the time at which the Old Testament canon was closed, there are many considerations which point to that of Ezra and Nehemiah, immediately after the return from Babylonian exile. (See BIBLE, EZRA, QUOTATIONS .)