The oldest, still existing religious book is also the oldest still existing literary works, the Epic of Gilgamesh from Sumer. It can be classified as a religious work because it contains mythological figures from their culture.
The oldest religious work from a still existing religious is the Hindu Rigveda. Hinduism is the oldest, still practiced religion in the modern world.
The Bible is the oldest, most translated, most quoted, most influential, and most respected book.
And certainly it is the book that has survived the most bans, burnings, and violent opposition. Unhappily, though, there is one superlative that can no longer be applied to the Bible. It is unlikely that it is any longer the most widely read book in the world.
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