The article deals with the records in the copy of the Bible kept in the collection of the Library of the Russian Academy of Sciences, which allow highlighting the personality and circumstances of the life of Elizabeth Magdalena (1580-1649), Duchess of Courland and Semigallia. Autographs of princely persons, marginalia and handwritten invectives reflect aspects of the dynastic solidarity of the princely houses of the Empire and the Baltic states, the spiritual world of the representatives of the princely elite and key episodes from the political history of the Duchy of Courland at the beginning of the 17th century. Particular emphasis is placed on the relationship between Elisabeth Magdalena and Duke Wilhelm, whose reign was associated with one of the most dramatic episodes in the life of Courland: the murder of the Nolde brothers in 1615.