It might help to consider and review some history for a fuller perspective.
Consolidation of written texts/books could be said to start with;
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The First Council of Nicaea (/naɪˈsiːə/ ny-SEE-ə; Ancient Greek: Σύνοδος τῆς Νικαίας, romanized: Sýnodos tês Nikaías) was a council of Christian bishops convened in the Bithynian city of Nicaea (now İznik, Turkey) by the Roman Emperor Constantine I. The Council of Nicaea met from May until the end of July 325.[4]
This ecumenical council was the first of many efforts to attain consensus in the church through an assembly representing all Christendom. Hosius of Corduba may have presided over its deliberations.[5][6] Its main accomplishments were settlement of the Christological issue of the divine nature of God the Son and his relationship to God the Father,[2] the construction of the first part of the Nicene Creed, mandating uniform observance of the date of Easter,[7] and promulgation of early canon law.[3][8]
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First Council of Nicaea - Wikipedia
As for "canon law", i.e. Bible content, the history and origins are a bit more murky;
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The Bible (from Koine Greek τὰ βιβλία, tà biblía, 'the books') is a collection of religious texts or scriptures, some, all, or a variant of which are held to be sacred in Christianity, Judaism, Samaritanism, Islam, the Baha'i Faith, and other Abrahamic religions. The Bible is an anthology (a compilation of texts of a variety of forms) originally written in Hebrew, Aramaic, and Koine Greek. These texts include instructions, stories, poetry, and prophecies, among other genres. The collection of materials that are accepted as part of the Bible by a particular religious tradition or community is called a biblical canon. Believers in the Bible generally consider it to be a product of divine inspiration, but the way they understand what that means and interpret the text varies.
The religious texts were compiled by different religious communities into various official collections. The earliest contained the first five books of the Bible, called the Torah in Hebrew and the Pentateuch (meaning five books) in Greek. The second oldest part was a collection of narrative histories and prophecies (the Nevi'im). The third collection (the Ketuvim) contains psalms, proverbs, and narrative histories. "Tanakh" is an alternate term for the Hebrew Bible composed of the first letters of those three parts of the Hebrew scriptures: the Torah ("Teaching"), the Nevi'im ("Prophets"), and the Ketuvim ("Writings"). The Masoretic Text is the medieval version of the Tanakh, in Hebrew and Aramaic, that is considered the authoritative text of the Hebrew Bible by modern Rabbinic Judaism. The Septuagint is a Koine Greek translation of the Tanakh from the third and second centuries BC; it largely overlaps with the Hebrew Bible.
Christianity began as an outgrowth of Second Temple Judaism, using the Septuagint as the basis of the Old Testament. The early Church continued the Jewish tradition of writing and incorporating what it saw as inspired, authoritative religious books. The gospels, Pauline epistles, and other texts quickly coalesced into the New Testament.
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The list of books included in the Catholic Bible was established as canon by the Council of Rome in 382, followed by those of Hippo in 393 and Carthage in 397. Between 385 and 405 CE, the early Christian church translated its canon into Vulgar Latin (the common Latin spoken by ordinary people), a translation known as the Vulgate.[53] Since then, Catholic Christians have held ecumenical councils to standardize their biblical canon. The Council of Trent (1545–63), held by the Catholic Church in response to the Protestant Reformation, authorized the Vulgate as its official Latin translation of the Bible.[54] A number of biblical canons have since evolved. Christian biblical canons range from the 73 books of the Catholic Church canon, and the 66-book canon of most Protestant denominations, to the 81 books of the Ethiopian Orthodox Tewahedo Church canon, among others.[55] Judaism has long accepted a single authoritative text, whereas Christianity has never had an official version, instead having many different manuscript traditions.[56]
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