The Book of Enoch

The Book of Enoch is an ancient Jewish apocalyptic religious text (300 - 200 BC), ascribed to Enoch, the great-grandfather of Noah. Enoch explains the origins of demons and giants; why some angels fell from heaven; why the Great Flood was morally necessary; and it also gives a prophetic exposition of the thousand-year reign of the Messiah.
Various Aramaic fragments have been found of the text in the Dead Sea Scrolls. There are also Koine Greek and Latin fragments which prove that The Book of Enoch was known to early Jews and Christians. The book of Enoch was also quoted by some 1st and 2nd century authors such as the author of the Testaments of the Twelve Patriarchs. It also appears that the New Testament authors were also familiar with some content of the story. A short section of Enoch is cited in the New Testament in the Epistle of Jude (1:14–15).
Although this book is not part of the biblical canon used by Jews, with the exception of Ethiopian Jews. Most Christian denominations and traditions accept the Book of Enoch as having some historical or theological interest. Only the Ethiopian/Eritrean Orthodox Church numbers the book among their Old Testament scriptures. Enoch is wholly extant only in the Ethiopian Ge'ez language from which this rendition is translated.