This lucid and admirably succinct book, written with imagination and warm feeling for the subject, is a distinctly welcome addition to the growing body of secondary literature on one of the finest, if unfortunately most prolix, of the great patristic theologians. It makes an excellent introduction besides offering an interesting new perspective. The approach adopted is to take, as an Ariadne's thread through the labyrinth of Maximus' thought, the twin notions named in the book's title. The approach risks over-simplification and does not entirely avoid it, but succeeds in giving a convincing and rounded interpretation of a thinker whose theology was based in a compound of ancient learning funnelled through a continuous tradition of biblical hermeneutics and church dogmatics. That theology may, I would think, be not improperly called ‘incarnational philosophy’ given the consistency and range of Maximus' interests. At the heart of it are the principles of union and distinction in the one Christ which fuelled Christological debate from the Nestorian controversy onwards; these are extended in a metaphysical scheme of simultaneous unity and distinction in general of things really united. Maximus is rightly remembered as the opponent of compromise with Copts and Jacobites who insisted on Christ's ‘one nature’ and who might have been satisfied with a Church reunion formalised in a watchword of ‘one energy’ or ‘one will’; but the reader is correctly warned at the beginning against an illicit emphasis on Maximus' ‘Chalcedonianism’, as also against modern ‘personalist’ theologies which draw on Maximus and the Cappadocians but distort a truly historical understanding of their thought. The five parts of the book deal with Maximus' logic and proceed to an analysis of his teaching on Trinity; on Christ; on the World, Church and Scripture; and finally on Ethics and the Spiritual Life. The last part moves more on the level of devotional commentary than theological analysis but is not, I judge, the worse for that. Warm though this book is towards the author's subject the difficult bits in Maximus are not overlooked. ‘Participation’ plays a prominent role in Maximus' explanatory categories, but what does it really amount to? Can that dreary analogy from heat transference that he is far too fond of explain anything? Again, the word gnomé means different things for Maximus, but what sense does it actually have when it is said that Christ has no gnomic will? The only understanding I have so far managed to arrive at is to say something like ‘Christ cannot have a gnomic will, since a gnomic will, as self-negating choice for non-being, is doubly anhypostatic both in the act of choosing and the object of choice: a deficiency and absence foreign to Christ's complete manhood.’ Maximus did not say those words and I doubt that he would ever have agreed to them. However, if gnomic will is enhypostatic then the assertion of its absence in Christ is, surely, ‘Apollinarian’. But the exponents of Maximus can safely be left to think about these and other matters of detail in interpretation. Here is a good book which will promote their discussion.