The Book of Enoch, written during the second century B.C.E., is one of the most important non-canonical apocryphal works, and probably had a huge influence on early Christian, particularly Gnostic, beliefs. Filled with hallucinatory visions of heaven and hell, angels and devils, Enoch introduced concepts such as fallen angels, the appearance of a Messiah, Resurrection, a Final Judgment, and a Heavenly Kingdom on Earth.