The book "Letters of Madame Guillon" is a collection of letters of the outstanding French mystic and writer Jeanne Marie Bouvier de La Motte de Guillon, who was one of the leading figures of French religious mysticism of the 17th century. This book is a collection of letters written by Madame Guyon during her imprisonment and exile, where she defended her religious views before the church authorities. This book is an excellent source for the study of Madame Guyon's biography and thought, as well as an important work in the context of religious literature. Madame Guyon's letters reflect her inner strength, faith and search for the Divine in the world around her.