Apocalyptic literature surfaces regularly when times are tough because a great number of people still cling to widely held beliefs in the bible which is still a best-seller after about 2000 years.
This type of literature arises out of a response to books in the bible that foretell or prophesy about events to come in the future. Since the book was written by a variety of authors and a variety of years ago to be specific, it actually occurs about every generation that apocalyptic literature re-emerges. The book of Mark in the bible references the growing expedience of great storms and quakes as signs of the end of the age. Many writers today would cite that all around us there are signs that the end is near.
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