Years ago, back in the seventies, I wrote a book on the eucharistic presence. In it I expressed my dissatisfaction with the account associated with transubstantiation, and my belief that recent attempts at other accounts had not succeeded. The book was given a friendly turn-down by a publisher, on the grounds that its theme was too much tied to Roman Catholicism to interest Christians of other traditions, while the Church of Rome itself would regard its contents as offensively heterodox. The verdict did not surprise me, the typescript went into honourable retirement on the upper shelf, and I turned my attention to other matters. But I was wrong to think myself rid of the topic. In the eighties, Stephen Sykes (now bishop of Ely) was editing a volume on sacrifice. The contributors were for the most part colleagues of his in the Department of Theology at Durham, but he asked me too for an essay, on eucharistic sacrifice in the middle ages, and I accepted the invitation. The topic – to my surprise – turned out to be rather a snakes-in-Ireland business, but I learned a good deal in the process, not least about the setting of the Eucharist. And then the Cambridge University Press, which was publishing the volume, expressed interest in publishing my book. And so it was that I set out upon a lengthy journey. The length was due in part to matters wholly alien to the life of the mind – administrative offices that were as uncongenial as they had been unsought. It was due in part to the need to complete other pieces of writing on which I had embarked.