The codex also called the "Devil's Bible" is a medieval manuscript that may have originated sometime between 1204 - 1230 from the Kingdom of Bohemia (now western Czechia). The codex is known for its very large size. It is 36 inches long, 20 inches wide, and 8.7 inches thick.
The codex is bound with wooden boards covered in leather with metal guards and fittings which contributes to its weight. There are 620 pages made out of vellum from the processed skins of animals. As an illuminated manuscript, the calligraphy in the codex is lavishly decorated. It is believed that all 600-plus pages were written by one Benedictine monk and that it took him almost 30 years to complete it.
The contents of the Codex include the Vulgate Bible and other works written in Latin. The Vulgate Bible is a 14th-century translation of the Bible. In addition to the Bible, there are five long texts.
One of the most unusual contents of the Codex Gigas is a unique illustration of the devil. There is a full-page portrait of the devil on one of the pages.
The Codex Gigas is now housed in the National Library of Sweden and it is stored in a climate-controlled case to protect it from damage.