According to myth, a Benedictine monk promised to write the book overnight to atone for his sins. When the task proved impossible, he asked the devil for help. This book, called the Codex Gigas (also known as the Devil’s Bible) is a medieval manuscript said to have been written 800 years ago. After an absence of 359 years, it has been returned to Prague, where it is believed to have originated.

Experts say that it took the monk 10 to 12 years to write that book, which contained 640 pages. 624 pages remain in fairly good condition.

Source: USA Today