Don't know what to buy your bishop for Xmas?

Richard Holloway is everything a bishop should not be: angry at the church, sceptical of dogma, committed to change. He even accepts that God might be a human invention. Yet the whole mood evoked by the former bishop of Edinburgh is positive. The "doubts" of his book's title refer not to any hesitant misgivings but to a robust and liberating agnosticism. Far from implying any lack of faith, his open attitude to doctrinal truth is what fuels Holloway's passionate commitment to Christian belief as "a habit of action" (Charles Sanders Peirce). Actions speak louder than words, and creeds should be judged by their practical outcome, not by how accurately they detail "the home life of God".

At one point, his conversion to theological pragmatism brings Holloway close to condemning the whole verbal side of his religion: "It is not just the boring talk, though there's been an ocean of that, it is the cruel talk, the judgement talk, the superior talk, the dismissive talk, the 'I have the truth and you don't' talk that is so crucifying. Isn't it time we dismantled all the calvaries our words have built for Christ and simply tried to follow him, preferably in silence?"

I am pleased to say he is not drawn into the silence he so eloquently commends. The words that make up Doubts and Loves bring a real sense that Christianity can still be a power for good, despite the many less-than-glorious aspects of its past.

The book begins by surveying the failure of the institutional church to face up to the challenge of modernism and postmodernism, a failure that has led to free-fall in church attendance and a rise in fundamentalism among the minority who still worship. Holloway draws on Thomas Kuhn's concept of a paradigm shift to analyse what has happened and what needs to happen in the resultant crisis.

In a second section, he grapples with the traditional Christian doctrines and shows how it is possible to "break a myth open" and uncover its meaning for today. He knows this will upset traditionalists and several times he calls on Paul Tillich for support. This betrays one of the few traces of defensiveness in the book. Holloway might do better here to be bolder and say that when we break open the myth, we create, rather than uncover, its meaning for us. In a sense this is what he actually does in the third and final section, where he blazes out his passionate belief-turned-radical-ethic like an Old Testament prophet. Neither church nor state is spared: "What is left of Christianity should be the practice of the kind of love that subverts the selfishness of power, whether it is the subtle power of spiritual or the brutal power of political institutions."

Holloway says that he has changed: "It is one of the deepest ironies of my life that I ended up in my 60s the kind of bishop that I attacked when I was a priest in my 30s." Well I first heard Holloway speak when he was barely out of his 30s. He brought a sagging conference to the edge of its seats with a challenge to the largely clerical audience to change their attitude to women in the ministry and to homosexuals. That was when hardly anyone in the church was addressing these issues. I hear the same Holloway today as I did then, and I shall not be alone in thanking God for his voice.

In Christ: A Crisis in the Life of God , Jack Miles brings about a transformation in doctrine - in this case the doctrine of God himself - every bit as dramatic as that proposed by Holloway. But he does it by the deceptively innocent means of simply taking the Bible at its word. Taking up the story where his Pulitzer prizewinning God: A Biography left off, he tackles the New Testament as if Jesus really were the God of the Jewish scriptures incarnate in a human life. He treats the Lord of the Old Testament (Yahweh) and the Lord of the New Testament (Jesus) as a single character with full psychological continuity and development.

This stunning treatment makes all our preconceptions about God take second place to what we are told in the biographical account of him that we call the Bible. Only three chapters into the epic tale, God has to ask Adam and Eve, "Who told you that you were naked?" So at that stage God is ignorant about what his creatures have been up to. A thousand pages or so later, in the second chapter of John's gospel, we are told that Jesus never needed to ask about people, since "He could tell what they had within". Miles comments that just after the creation, when his physical strength was at its height, God was still ignorant; years later, as Jesus, "he is physically quiescent, but his mental powers have grown apace". So much for the philosophers' changeless and omniscient deity.

For traditionalists of a moral or religious turn of mind, there is yet worse to come. On Miles's reading, the reason Jesus underwent a baptism of repentance at the hands of John the Baptist was that God had a lot to repent of. In the Garden of Eden he had let Satan outwit him and in his anger had betrayed humankind, condemning it to death. Then over many centuries he repeatedly broke his promise to redeem Israel and restore the fortunes of Zion. Even now, as the incarnate God predicted his people's annihilation by the occupying Roman forces, he knew he would not lift a finger to save them.

Faced with these failures, the biblical God chose not only to become a Jew, but to subject himself to death by the very crucifixion that so many of his people were to suffer at the Romans' hands. His subsequent rising from the dead would not save Judaea from Caesar's brutality in the short term, but it would make good the catastrophe of Eden and restore to humans long-term the immortality God's earlier bungling had cost them.

The author says his literary approach has its own integrity and does not entail a misconstrual of its story. Just as we can appreciate Homer without believing in the gods of Olympus, so Miles (who is himself a practising Christian of long standing) sees a real value in the Bible for those who approach it as a work of literature, even without commitment to it as a religious text. Surely he is right. But the faithful should also try reading it this way as well. Here is narrative theology at its most daring: Christ dies to take away the sins of God, as well as the sins of the world. Give your bishop a copy for Christmas.

The first thing that struck me about the final book under review was its size. I knew that Christianity: Two Thousand Years was a series of lectures by leading church historians, and having just seen the medieval cover picture, I expected a coffee-table volume lavishly illustrated in colour from every Christian century. What I received was a pocket-book less than 7 by 5 inches, with three maps and five half-tone pictures. All right, it will teach me to read the publisher's blurb more carefully; but surely OUP could have done better than this with the opportunity offered by this volume?

The nine lectures themselves must have been occasions to relish. As a science undergraduate I would slip away from the labs to go and hear Kallistos Ware (who contributes "Eastern Christianity") enthuse over the characters who were the first Christian monks, and I sat through Henry Chadwick's lectures on the early church (also his topic here) two years running for the sheer pleasure of reliving these distant events in his company. But unrevised talks seldom make the best books, and Henry Mayr-Harting admits that the free hand given to contributors left some glaring gaps in this 2000-year story, for which his own editorial introduction and the bishop of Oxford's brief "Prospect" at the end barely make up.

In general, the content is predictable. For instance, Averil Cameron on "Late antiquity" chronicles the swift coming together of the powers of church and state following the emperor Constantine's decision to back the Christian cause in AD 312. By the end of the century, polytheistic religion and Christian heresy were both subject to punishment by the secular arm, and senior bishops such as Ambrose of Milan and John Chrysostom could be by turns the scourge and panegyrists of emperors and their families.

Mayr-Harting's own chapter on "The early Middle Ages", like a number of the others, is simultaneously a guide to some good recent literature on the period, a useful bonus to his introduction to some of the livelier characters of the time, from Gregory the Great via Charlemagne to Gregory VII. There were fascinating bishops in those days, such as Ethelwold of Winchester, who had a passion for building organs, and Michael of Regensburg, who lost a battle against the Hungarians in the 940s and returned to his diocese "minus an ear, but with greatly enhanced kudos".

It would be foolish to blame an historical overview for looking backwards, but coming to this book straight from reading Holloway and Miles, the difference in tone is striking. When those two authors look back, the reader still senses the drive forward, the urgency of something important now. For the most part Christianity: Two Thousand Years , even the pages devoted to "The twentieth century" (by Adrian Hastings), lack this. The past is brought engagingly to life, but somehow remain detached.

A notable exception is Jane Shaw's challenge to a contemporary view of the Enlightenment and her own analysis of "The late seventeenth and early eighteenth centuries". She uses this to highlight issues that for her - "a woman and a priest, a scholar, and a person of faith" - still need resolving. It is the one chapter that forced me to think and to question in a book that otherwise I was content just to sit back and enjoy.

The Revd Anthony Freeman is managing editor, Journal of Consciousness Studies .