An astonishing reversal of fortunes is taking place in British Jewry that will not only affect its future, but also the way in which Jews are perceived generally.
According to figures just produced by the community's representative body, the Board of Deputies, marriages within the strictly Orthodox (Charedi) community are expected to account for more than half of all Jewish marriages in the UK within ten years.
This is a result of the high birthrate amongst Charedi families - who are a small proportion of British Jewry, yet are producing at least four out of ten Jewish children born today. The Board expects strictly Orthodox births and marriages to outstrip those within the rest of the community within a matter of decades.
It is astonishing for two reasons. First, that not so long ago, the ultra-Orthodox were such a small percentage within British Jewry that it was assumed they would fade away with time.
It was their communities that had suffered most in the Nazi extermination camps.
A remnant had survived, some seeking refuge in the UK, but it was assumed that in the brave new world of pluralism, with people of many races and faiths inter-mingling freely, they would be like the Amish, a curious throw-back to a previous era. Never did anyone think they would re-energise and start heading towards a position of dominance within British Jewry
In part, this was precisely a reaction to the Holocaust. There was a sense of mission to replace the six million Jews who had been murdered. Large families were encouraged, and because this coincided with more assimilated Jews having a lower number of children, the effect has been rapid ultra-Orthodox expansion at a time of contraction amongst other Jews.
The other reason for surprise is because, until now, the rest of British Jewry has generally been a highly integrated within society at large. Its members have kept up their Jewish identity and traditions, but have also been thoroughly immersed in wider life.
They range from comedian David Baddiel, to broadcaster Vanessa Feltz, to actress Maureen Lipman, to historian Simon Schama, to politician Ed Milliband, to TV doctor Robert Winston, to businessman Alan Sugar, to jockey Sam Waley-Cohen. They have managed to live in two worlds simultaneously, and see no conflict between their Jewishness and Britishness.
By contrast, most Charedi Jews have tended to be engaged primarily in their own internal affairs. Some exceptions stand out, such as Paul Reichmann, who developed Canary Wharf in East London, and a few who have become involved in civic affairs as local councillors for their areas.
Still - looking at what has been happening in other faiths - perhaps it should have been expected, with a revival of the 'religious right' occurring in Christianity, Islam and Hinduism. Not that the progressive wings within both Judaism and other faiths have given up their principles. They are still active and have been campaigning vigorously for liberal goals such as female clergy, gay rights and mixed-faith weddings, and often achieving them. But whereas it was assumed that the forces of Orthodoxy were on the retreat, it is clear that this may be a misjudgement, certainly within British Jewry.
As for the consequences, it will mean change for everyone: liberal Jews will have to take account of the numbers shift and share communal structures with the ultra-Orthodox, even though their lifestyles are radically different. The ultra-Orthodox will have to play a more public role - within Jewry and wider life - if they are to step up to the responsibilities that their growing size will give them. The British public will develop a new perception of Jews, or rather a more diverse one, not only the anglicised unbearded Lionel Blue, but also the bearded Charedi with black hats and gabardines.
But while appearances may vary, the underlying values will be the same - 'Love your neighbour as yourself' (Leviticus 19.18) - which not only unites different types of Jews, but also unites people of many different faiths and belief-systems.