An apocalypse is a disclosure or revelation of great knowledge. In religious concepts an apocalypse usually discloses something very important that was hidden or provides what Bart Ehrman has termed, "A vision of heavenly secrets that can make sense of earthly realities". Historically, the term has a heavy religious connotation as commonly seen in the prophetic revelations of eschatology obtained through dreams or spiritual visions. It is believed by many Christians that the biblical Book of Revelation depicts as an "apocalypse", the complete destruction of the world, preceding the establishment of a new world and heaven. However, there is also another interpretation of the Book of Revelation in which the events predicted are said to refer to the destruction of Jerusalem in A.D. 70 by the Roman armies of Titus. This second view is known as the Preterist view of eschatology.