An apocalypse (Ancient Greek: ἀποκάλυψις apokálypsis, from ἀπό and καλύπτω meaning “uncovering”), translated literally from Greek, is a disclosure of knowledge, i.e., a lifting of the veil or revelation. In religious contexts it is usually a disclosure of something hidden.
In the Book of Revelation (Greek: Ἀποκάλυψις Ἰωάννου, Apokalypsis Ioannou – literally, John’s Revelation), the last book of the New Testament, the revelation which John receives is that of the ultimate victory of good over evil and the end of the present age, and that is the primary meaning of the term, one that dates to 1175.
Today, it is commonly used in reference to any prophetic revelation or so-called end time scenario, or to the end of the world in general.
The revelation may be made through a dream, as in the Book of Daniel, or through a vision, as in the Book of Revelation. In biblical accounts of revelations the manner of the revelation and its reception is generally described.
According to the Book of Daniel, after a long period of fasting, Daniel is standing by a river when a heavenly being appears to him, and the revelation follows (Daniel 10:2ff).
John, in the New Testament Book of Revelation (1:9ff), has a similar experience, told in similar words. Compare also the first chapter of the Greek Apocalypse of Baruch; and the Syriac Apocalypse of Baruch, vi.1ff, xiii.1ff, lv.1–3. Or, as the prophet lies upon his bed, distressed for the future of his people, he falls into a sort of trance, and in “the visions of his head” is shown the future. This is the case in Daniel 7:1ff; 2 Esdras 3:1–3; and in the Book of Enoch, i.2 and following.
Typically, the messengers of the apocalyptic revelation are described as angels. In the Bible, God may give a revelation or instructions through the medium of these heavenly messengers; they act as the seer’s guide. God may Himself give a revelation, as is shown in the Book of Revelation through the person of Jesus Christ. The book of Genesis speaks of the “angel” bringing forth the revelation.