When Marie Bosse was arrested in Paris, in January 1679, among her possessions was a copy of an unusual magical text. The Enchiridion Leonis Papae—Pope Leo’s Handbook—has since acquired notoriety as a work of ‘black magic’, largely due to its association with the subsequent ‘Affair of the Poisons’, and the aura it acquired among 19th-century occult revivalists.

The earliest extant text of 1633 is a clerical handbook belonging to the same genre as the 1614 Rituale Romanum, to which is appended material that would come to distinguish the Bibliothèque bleue grimoires; a blend of folk belief and Church tradition which blurs the line between orthodox religious praxis and sorcery.

Our new edition is translated into Modern English from the French and Latin of the 1633; it presents the various prayers, exorcisms and invocations in Latin and English, and includes new rubrics illuminating how the text would have been employed by a clerical or lay practitioner of the day.