The canon: Christianity in the West 1400-1700. By John Bossy

Startling originality is a rarity in history writing. It is perhaps particularly rare when writing the history of religion, where it is so hard to escape the constraints of dogma and institutional structure. In writing the history of the Reformation, for example, it is well- nigh impossible to disentangle what happened from what Protestants and Catholics would like to have happened. John Bossy's Christianity in the West (1985) cut a swath through these complexities, breaking away from the institutional history of the Church to give us something that is genuinely a history of Christianity.

Bossy's interests lay not with institutions, but with the Church as "a body of people, a way or ways of life". His erudition and the breathtaking range of his ideas failed to eclipse either his sense of humour or his candid appreciation of human nature, as he explored what happened to religion between 1400 and 1700.

On one level, we may try to claim Bossy as a revisionist historian of the Reformation. He did, after all, demonstrate that the late medieval Church was not a burden to its congregations, and he argued that we are wholly mistaken to see Christianity as arriving in any intelligible form in the West only in the 16th century. But he found "Reformation" unsatisfactory as a term, not just because it wrongly implied that "bad" religion was giving way to "good", but because it had little application to "actual social behaviour" and little or no sensitivity to "thought, feeling or culture".

This book transcended tired debates over whether Protestants or Catholics were more popular, successful, articulate or authoritarian. Bossy cared more about how religious change affected ritual, kinship and charity. He saw how some developments shaped Protestantism and Catholicism alike, such as the spread of catechisms "reducing Christianity to whatever could be taught and learnt". He explained how ideas about sanctity in the medieval Church could be discovered in the example of St Guinefort, the French saint who also happened to be a dog, and showed why even Calvinism could not bring itself to surrender its saints and martyrs. He could recognise "family resemblances" between different sorts of Christianity and see how apparently opposing doctrines could be accompanied by very similar social consequences.

Christianity in the West shows what can be done by a historian of religion who is willing to shed the prejudices of religious culture while still understanding its processes and preoccupations. Nobody else has ever achieved this astonishing marriage of sociology with theology and produced such an incisive analysis of religion within society. This book is also a vastly informative and entertaining read, moving from eucharistic doctrine to the significance of the invention of the fork, from Milton on sin to Durkheim on sanctity, from Erasmus' views on polyphony to Luther's ideas about the Jews, from the place of football within carnival to the invention of opera.

In the end, Bossy suggests that "Reformation" is an inadequate description of how, between 1400 and 1700, religion and society were recreated as separate entities and Christianity moved from being "a body of people" to being "a body of beliefs". His conclusions are open to question; his approach is still, 25 years on, as original and as inspirational as ever.