In July 1930 Bonhoeffer wrote in the preface to the published version of his doctoral dissertation: ‘The more theologians have considered the significance of the sociological category for theology, the more clearly the social intention of all the basic Christian concepts has emerged. Ideas such as “person”, “primal state”, “sin” and “revelation” are fully understandable only in relation to sociality.’ Two recently published works, a translation of Bonhoeffer's 1933 Christology lectures and John A. Phillips' study of Bonhoeffer's theology, give occasion for examining the meaning of this statement and its importance in understanding Bonhoeffer's thought.