The Book of Jasher (Sepir Ha Yasher) is an apocryphal book, and this one in particular is a translation of a Hebrew book printed in 1613. The Hebrew title of the book means 'Book of the Upright', but the title was at some point, treated as a proper name (Jasher), and that continued. The actual text of the book covers the creation of the world to the death of Moses. This translation was originally published in 1887. Note: E.J. Goodspeed, Modern Apocrypha, Famous "Biblical" Hoaxes, cites several reviews from the late 18th and early 19th century that declared this book to be "a shameless literary forgery" (J. Baskette).
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