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The scribe was a monk who broke his monastic vows and was sentenced to be walled up alive. In order to forbear this harsh penalty he promised to create in one single night a book to glorify the monastery forever, including all human knowledge. Near midnight he became sure that he could not complete this task alone, so he sold his soul to the devil for help. The devil completed the manuscript and the monk added the devil’s picture out of gratitude for his aid.
Despite this legend the codex was not forbidden by the Inquisition and was studied by many scholars.
It is said that this particular handwriting has not been found anywhere else.
Many aspects of the legend most probably originated in truth, however due to the large portrait of Satan which would have been unique at the time, it is likely that the legend altered the truth so that the story could be retold in a more interesting way. Anyone from the time who looked at the book would most likely be drawn to the portrait of Satan, thus getting the impression that this was one of the book’s focal points, explaining why people would believe that the monk made a pact with the devil. What many would have failed to see was that the page opposite this portrait was what is believed to be a picture of the kingdom of heaven. Now, many believe that double page spread was made to symbolize the fact that good and evil exist side-by-side, and nothing sinister.
What most likely happened is that the monk requested to produce the book in solitude, probably over a period of at least twenty years. Many monks would have used the copying of sacred texts as a method of purging their soul of evil, which could explain the monk’s motivation. The part of the legend that says that he was walled up alive as a punishment was probably a misinterpretation of his name, which is believed to be in Latin ‘Herman Inclusus’ or in English ‘Herman the Recluse’. This misinterpretation is understandable as the word ‘Inclusus’ could refer to either the punishment or voluntary solitude.

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