When British Jews were asked what was important to them in the largest ever communal survey six years ago, belief in God came only 16th on a list of 20.

Barely more than half — 52 per cent — told the Institute for Jewish Policy Research that it was important to them.

Similarly, among the biggest diaspora community, only a third of American Jews professed belief in the “God of the Bible”, according to the Pew Research Centre last year, compared with 80 per cent of Christians.

More than half opted for a vaguer belief in a “higher power”.

In this last book, This Is Not the Way, Liberal Rabbi David Goldberg contended that Jews who respected ancestral custom but no longer believed in “the God of Judaism” formed the overwhelming majority.

But for the former chief executive of the Movement for Reform Judaism, Rabbi Professor Tony Bayfield, as he states in his new book, “God won’t leave me alone”. Published this week, Being Jewish Today is the culmination of nearly half a century in the rabbinate — an attempt to offer a theology for modern Progressive Jews.

“What the book says,” he explains, “is that if you can’t believe in the lack of human involvement in sacred books; if you can’t believe that the Torah is extra-historical and somehow appeared to Moses and Moses acted as the stenographer; if you can’t believe the righteous are rewarded and prosper and the wicked suffer and are punished; if you can’t believe that God intervenes by suspending the laws of nature to create miracles; if you can’t believe that a good God could intervene but chooses not to in the suffering of untold millions of innocent people — then let’s go on a journey together. Let’s see if people like us can construct some kind of viable theology.”

Anglo-Jewish rabbis are not noted for their literary output. As the book notes, rabbis in the UK have largely ceded their “intellectual role”, with the right devoted to ritual minutiae and the left to the pastoral preoccupation with building “warm, inclusive” communities.

His book is infused with a wide range of reading, from the often daring flights of rabbinic midrash to contemporary thinkers such as the Israeli bestseller Yuval Noah Harari to the radical American theorist Judith Butler. The common view that Judaism doesn’t do theology is, he shows, mistaken; it’s that, rather than systematic philosophy, the rabbis generally preferred to express their thoughts through story.

He draws too on personal experience, recalling in the book how, for instance, he was confronted with the raw pain of the world when a young boy was run over and killed on the way to being taken to the communal Seder he was about to conduct as a student rabbi in the small community of Harlow.

Or how a rabbi, when trying to console him on the premature death of his wife Linda from cancer, told him that, “Some people are so important to God, that He calls them to be with Him.” Which prompts the book’s comment that silence is preferable to “blasphemous platitudes or dogmatic clichés”.

His study, overlooking the garden of his Hampstead Garden Suburb home, bears witness to the breadth of his library. But one set of volumes not quoted from are the bound volumes of match programmes of his beloved West Ham, although there is a fleeting reference in the book to his “claret and blue grandchildren”.

Now 73, he qualified as a rabbi in 1972, having opted for the pulpit rather than pursuing a doctorate in criminology. After 11 years with North-Western Surrey Reform Synagogue, he became director of the newly established Sternberg Centre for Judaism in Finchley in 1985 and then professional head of the Reform movement until his retirement in 2011.

As he recalls in the book, his mother-in-law, once asked what he did, replied that he could have done anything but chose to be a rabbi. “He must be very religious,” said her questioner. “No,” she replied, “he’s Reform.”

Demonstrating that religious and Reform are not mutually exclusive is precisely his aim. His own family has an extensive record of commitment. Linda was headteacher of the first Progressive day school in the UK, Akiva. Their elder daughter Lucy is now chair of governors of the school, where their son Daniel’s three sons have been schooled. Younger daughter Miriam is rabbi of one of the Reform’s biggest communities, Finchley.

And granddaughter Chessy (Francesca), now starting university, has ambitions of becoming a cantor.

“The old slur that Reform is just a step before total assimilation really isn’t true,” he says.

Writing the book was “a difficult and painful process,” he says. He was first commissioned to do it by the Reform movement when he became its honorary president on retirement. One of the movement’s then board members, Charles Kessler, told him, “We want you to give the movement some intellectual bottom”.

The movement, however, changed its mind and decided it didn’t want it. “Which was sad but in the end, I have to look back and say it did me a favour,” he says.

The 180,000 words of material became a course reader for the rabbinic students he taught at Leo Baeck College. But two years ago, after he had edited a volume on Christian-Jewish relations, his partner Jacqui Fisher said, “Now is the time to go back to your book and go for the mainstream publisher you always wanted.”

He was put in touch with Robin Baird Smith of Bloomsbury (whose list includes the Harry Potter series). “In a very early incarnation, he published Louis Jacobs and discovered Lionel Blue”. Mr Baird Smith gave him a choice of either aiming for an academic text which “sells for £70 and sits on university library shelves” or trying to address “the intelligent general reader, primarily but by no means exclusively Jewish”.

Opting for the latter, Rabbi Bayfield pruned the text almost in half to just over 300 pages.

“In the process of working with Robin,” he says, “it became clear I wasn’t writing a polemical book. I wasn’t at all interested in doing British Jewish politics. The last thing I wanted to do was to disturb people’s traditional faith.”

But he does challenge the “most articulate and philosophically educated” of all defenders of traditional Orthodox doctrine, his Cambridge contemporary, Jonathan Sacks.

Rabbi Lord Sacks, he argues, takes an all-or-nothing approach, seeing either acceptance of the divine authority of both the Written and Oral Torah or secular rejection of sacred texts. Instead, for two centuries, Jewish thinkers have been formulating an “intermediate position”, Rabbi Bayfield argues.

For him, the Torah reflects our ancestors’ interpretation of their religious experiences, not the experience itself.

God, he believes, neither intervenes in history nor suspends the laws of nature but stirs human beings to help redeem the world through acts of justice and compassion.

Some may be surprised to find a Progressive rabbi turning to the kabbalists of 16th century Safed to define his faith. He was inspired by the mystical idea that Creation necessitated also an act of divine withdrawal.

When he published a Reform religious manifesto some years ago, he found that the main interest was in “the Reform position on Sabbath observance, kashrut and conversion.

“I became more and more frustrated with a community, with Reform Jews, who were only interested in those things and how that related to the Orthodox position.”

But he took confidence from sermons he had given over the years that people were interested in the bigger questions — “what’s it all about, what’s it all for, why are we carrying on?”

While some today ground their Judaism in the fashionable idea of tikkun olam, “repair of the world”, he is wary of the term. “I think there is a tendency in many liberal circles to use tikkun olam as a catch-all term for social justice and then label anything they do in that area as being Jewish simply because they call it tikkun olam,” he says. Rather than root it in the “ethical substance” of rabbinic debate.

“For me, the USP [unique selling point] of rabbinic Judaism is the interrogation of the text and teasing out of meaning and purpose of ethic and belief through a process of discussion and debate — and frequent disagreement.

“I regard contemporary Reform Judaism as four-square within that tradition of rabbinic Judaism”.

He is conscious of writing for a community that is currently “riddled by fear and anxiety”, as the book describes it, feeling internally threatened by falling numbers and externally by “never-ending antisemitism”.

On the response to antisemitism, he cites a favourite joke of Rabbi Lionel Blue. “There is a tsunami heading for Tel Aviv. The Christians go to their churches and pray, ‘Dear God, please save us’. And the Muslims go to the mosques and pray that Allah will take them to heaven to be with Him.

“And the Jews go to synagogue and say, ‘Dear God, it’s going to be difficult living under five metres of water’.”

We may be fortified by a long history of coping with adversity. But Rabbi Bayfield does not believe that survival for its own sake is “either sociologically or theologically sufficient in itself. It is the continuing pursuit of meaning and purpose — albeit down here in the five metres of extremely murky water.

“I am not sure you can survive as a Jew down the generations unless there is something more than survival.”

Being Jewish Today — Confronting the Real Issues is published by Bloomsbury at £18.99