The authorship of the books of the Old Testament is a complicated question, such that authorship studies constitute a significant and much-disputed field in Old Testament scholarship. A few books can be confidently assigned to particular authors, but in most cases, authorial attribution is difficult because of the antiquity of the texts, their frequent lack of internal claims of authorship, and in some cases, their apparent structure as composite works. While some scholars offer support for traditional authorship claims, others argue that there were likely many other authors involved, in addition to redactors and compilers who brought the canon into its final form.

Many Old Testament books have authorship attributions assigned by long-held traditions. These include the practice of referring to the first five books (the Pentateuch) as “the law of Moses,” with the assumption that they are almost entirely the work of Moses himself. The internal evidence in many Old Testament texts is often not strong enough to decide the matter of authorship, so scholarly opinion on the topic ranges from defenses of traditional authorship to arguments for a much more complicated scenario involving multiple authors, redactors, and compilers. One example of the latter position is the influential JEDP hypothesis of the Pentateuch’s composition, which argues against Moses’s sole authorship and instead makes a case, based on differences in vocabulary and thematic content, that the first five books of the Bible represent the interwoven contributions of at least four main sets of writers, known as the Yahwist (represented by J), the Elohist (E), the Deuteronomist (D), and a Priestly (P) writer.