Mosaic authorship is the Judeo-Christian tradition that the Torah, the first five books of the Hebrew Bible/Old Testament, were dictated by God to Moses. The tradition probably began with the legalistic code of the Book of Deuteronomy and was then gradually extended until Moses, as the central character, came to be regarded not just as the mediator of law but as the author of both laws and narrative.

Mosaic authorship of the Torah was unquestioned by both Jews and Christians until the European Enlightenment when the systematic study of the five books led the majority of scholars to conclude that they are the product of multiple authors throughout many centuries.

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