The Bible has not been “discovered” in any archaeological sense. It has always been read, copied and redistributed from the time the first book was written down. Over time, as God inspired more books, the collection of books that make up the Bible grew. It took its current form sometime around AD 100.
Some ancient copies of biblical books have been discovered. But these are copies of books we already know about. The most famous such discovery was the Dead Sea Scrolls in 1947. These scrolls included parts of all of the books in the Old Testament apart from Esther.
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