Heinrich Suso, the Rhineland mystic, was born at Constance and early entered the Dominican order. A mystical experience at the age of eighteen set him on the path of asceticism, but a later one, between 1335 and 1340, led him to abandon self-mortification and to embark on an active career as preacher and spiritual adviser. As a result of attacks on some of his teachings and on his personal character, he was transferred to Ulm in 1348.

During his period of studies in Cologne, Suso had come into contact with Johannes Tauler and also came under the influence of Meister Eckhart. Indeed, in Das Büchlein der Wahrheit (The Little Book of Truth, c. 1327) he was bold enough to defend Eckhart against the doctrinal charges leveled against him, setting Eckhart's disputed doctrines alongside other quite orthodox statements made by him and providing interpretations that did not entail...