The monumental work of renowned twentieth-century Swiss ecclesiologist Charles Journet, The Church of the Word Incarnate, is among the most comprehensive and spiritually profound studies of the mystery of the Church. Presented here for the first time in English translation is Journet's complete five-volume "essay in speculative theology," in which he undertakes a Thomistic presentation of the Church in light of her four causes—efficient, material, formal, and final—corresponding to her four marks of apostolicity, catholicity, unity, and sanctity. In this third volume, Journet extends his treatment of grace and charity as the Church's "soul," begun in the prior volume, to consider the integral unity of the "body" of her visible members. This holistic account of the Church as essentially both invisible and visible provides the setting for his further reflections on schism and heresy, the relationship of sinners to the sanctifying Church, and the situation of those who have not yet received the Gospel. The volume culminates with Journet's examination of the Church's properties of catholicity and unity, in which he explains how all supernatural life that lies beyond the Church's visible frontiers can nonetheless be recognized as belonging to the Church.