A biblical canon or canon of scripture is a set of texts (or "books") which a particular religious community regards as authoritative scripture. The English word "canon" comes from the Greek κανών, meaning "rule" or "measuring stick". Christians became the first to use the term in reference to scripture, but Eugene Ulrich regards the idea as Jewish.
Most of the canons listed below are considered by adherents "closed" (i.e., books cannot be added or removed), reflecting a belief that public revelation has ended and thus some person or persons can gather approved inspired texts into a complete and authoritative canon, which scholar Bruce Metzger defines as "an authoritative collection of books". In contrast, an "open canon", which permits the addition of books through the process of continuous revelation, Metzger defines as "a collection of authoritative books".
These canons have developed through debate and agreement on the part of the religious authorities of their respective faiths and denominations. Believers consider canonical books as inspired by God or as expressive of the authoritative history of the relationship between God and his people. Some books, such as the Jewish-Christian gospels, have been excluded from various canons altogether, but many disputed books—considered non-canonical or even apocryphal by some—are considered to be Biblical apocrypha or deuterocanonical or fully canonical by others. Differences exist between the Jewish Tanakh and Christian biblical canons, although the Jewish Tanakh did form the basis for the Christian Old Testament, and between the canons of different Christian denominations. In some cases where varying strata of scriptural inspiration have accumulated, it becomes prudent to discuss texts that only have an elevated status within a particular tradition. This becomes even more complex when considering the open canons of the various Latter Day Saint sects—which are usually viewed as divergent from biblical Christianity (and moreover, Judaism)—and the scriptural revelations purportedly given to several leaders over the years within that movement.
Rabbinic Judaism (Hebrew: יהדות רבנית) recognizes the twenty-four books of the Masoretic Text, commonly called the Tanakh (Hebrew: תַּנַ"ךְ) or Hebrew Bible. Evidence suggests that the process of canonization occurred between 200 BC and 200 AD, and a popular position is that the Torah was canonized c. 400 BC, the Prophets c. 200 BC, and the Writings c. 100 AD perhaps at a hypothetical Council of Jamnia—however, this position is increasingly criticised by modern scholars. According to Marc Zvi Brettler, the Jewish scriptures outside the Torah and the Prophets were fluid, different groups seeing authority in different books.
The book of Deuteronomy includes a prohibition against adding or subtracting (4:2, 12:32) which might apply to the book itself (i.e. a "closed book", a prohibition against future scribal editing) or to the instruction received by Moses on Mt. Sinai. The book of 2 Maccabees, itself not a part of the Jewish canon, describes Nehemiah (c. 400 BC) as having "founded a library and collected books about the kings and prophets, and the writings of David, and letters of kings about votive offerings" (2:13–15).