This commentary expands Johannine studies in two directions. First, drawing on the methods of literary criticism, it gives new force to a view which is both ancient and modern—that John's gospel, far from being a poorly-edited mixture of sometimes-conflicting traditions, is in fact a coherent unity, an account of Jesus which, however diverse its sources, is a finely-chiselled work of art. Second, it indicates that the unity of John's gospel is founded ultimately not on history or theology but on spirituality. This too corresponds to a view which is both very old—John was always known as the spiritual gospel—and very recent. The present study spells out that idea in new detail. It indicates that the account of Jesus is so written that the tensions and complexities of the text reflect the tensions and complexities of human life, providing the reader not only with an account of Jesus but also with an anthropology—a map of the development of the human spirit.