The completion of a book is a time for stock-taking. Why have I written on this topic, and not another? How have I managed to complete it, given the ever-growing demands teaching and administrative duties make on the time of an academic?

The topics explored in this book are at the very centre of the concerns of anyone interested in earliest Christianity and, indeed, in Christian theology. I have tried to approach them from fresh angles and, where possible, in the light of new evidence. So I have spread my net more widely than is often the case. The questions discussed have captured my interest for a variety of reasons. In some cases I think that I have found new paths through well-traversed territory. In others, I have become dissatisfied with the standard answers.

Chapter 2, ‘Jesus and Gospel’, is a considerably extended version of the Inaugural Lecture I gave as Lady Margaret's Professor of Divinity in the University of Cambridge on 27 April 2000. In my introductory remarks I referred to the debt I owe to my two predecessors in the Cambridge Chair, Professors C. F. D. Moule and Morna Hooker, who were both present.

An earlier version of Chapter 5, ‘The Law of Christ and the Gospel’, was one of eighteen seminar papers given as part of the celebrations of 500th anniversary of the establishment of the Lady Margaret's Professorship in 1502.