When the Centre for Jewish Life holds its next Friday night dinner for young adults at a smart London hotel at the end of the month, there will be a pause in the flow of wine and chatter. Special tributes will be paid that night to the victims of the kosher supermarket attack in Paris.
Last week's events would have been more sharply felt by many of those who go to the CJL, a West End-based club with a large cosmopolitan clientele. Rabbi Yosef Vogel, its managing director, reckons that of the 5,000 young people on its books, around a fifth are from France.
He said the centre would continue to deliver "a strong message of unity and pride. This is the only way you can combat something like this".
If Jews were to bow to fear by shying away from such events it would only give incentives to their enemies, he said.
Whatever the apprehension about the possibility of a similar incident here, it did not show in any drop-off in synagogue numbers at the weekend.
Assurances by police and community organisations of increased security steadied nerves.
Anne Gordon, chairman of one of the United Synagogue's largest communities, Borehamwood and Elstree, said that "apart from the sombre atmosphere, it has been very much business as usual".
At Finchley Reform Synagogue, Rabbi Miriam Berger rejected any counsel of fear. "What if it had been a kosher supermarket in Temple Fortune, then would I believe we are unsafe? Would I have needed to be in the supermarket or lost a loved one, then would I admit our vulnerability?" she said in her sermon.
"No, and mostly because I'm not sure what good it does us. A community in Paris so terrified they cancelled their Friday night service - who wins? We cannot allow this culture of fear to seep back into our psyche. Not only does it damage the strength of the community, but it paralyses us from doing what is right."
Big synagogues such as Hampstead Garden Suburb United and the Masorti New North London also drew full houses.
During a sermon at HGS, Emeritus Chief Rabbi Lord Sacks touched on the theme of his next book - about the roots of religious violence.
A shul-goer on security duty at a north-west London synagogue said services had remained as full as ever.
"I think the feeling was that we were on such high alert, nothing was likely to happen this weekend," he said.
At New North London in Finchley, barmitzvah guests included Paris residents who live close to the attacked supermarket. A psalm was recited in French and Hebrew.
Chief Rabbi Ephraim Mirvis and Reform Senior Rabbi Laura Janner-Klausner attended Sunday's unity rally in Paris, while Board of Deputies president Vivian Wineman and Jewish Leadership Council chief executive Simon Johnson were among those who were at a solidarity event in Trafalgar Square.
On Tuesday, Mr Wineman and Board chief executive Gillian Merron signed the condolence book at the French embassy in Knightsbridge.
United Synagogue president Stephen Pack, in a letter to Roger Cukierman, the head of the French Jewish representative body Crif, said that there had been an "outpouring of emotion in response to attacks that are as horrific as they are indefensible.
"In each of our synagogues this Shabbat we took time to remember and pray for the victims, their friends and families".
The Muslim Council of Britain sent a message of support to say that it was "united in solidarity with the Jewish community".
The MCB's secretary-general Dr Shuja Shafi also wrote to the executive director of the Union of Orthodox Hebrew Congregations Chanoch Kesselman. "We must not allow these agents of hate to divide us; I hope we can redouble our efforts in solidarity," he wrote.
Mr Kesselman replied: "Jews and Muslims have had, and continue to have, mutual respect for each other. The fanatical hate preachers will not change that. Neither will the satirists of anti-religion who respect no one."
In kosher food shops around the country the mood among staff and shoppers was defiant in the face the attack on the Paris supermarket.
"We are happy and proud to be selling kosher food and have the word 'kosher' outside our shop. I'm not prepared to hide," said Richard Hyman, owner of Manchester's longest established kosher shop, Titanics.
"People are still coming in. The customers have been fine. All the regulars have been in - they've been talking about it, but most people are just saying 'we're not going to be intimidated'."
Rivki Rokach, manager of Golders Green supermarket Kosher Kingdom, said: "We reassured our staff and have implemented a few internal security measures, but we're carrying on as usual. We're in contact with CST on a regular basis.
"You can't function in panic mode. It's never healthy. We just have to be realistic and do what's sensible. Look at what happens in Israel on a weekly basis, and the country still functions very well. I think we should take an example from them."
Closing would mean giving in to terror, she said.
"Some people are very defiant and some are a bit nervous. People are still shopping, people still need food. They're aware, but life carries on. It's always the week after these kind of things that people are edgy, and then things go back to normal."
Customers at Kosher Kingdom in Golders Green were also steadfast in their determination to carry on as normal.
Shopper Trevor Leigh said he had gone to the store despite suggestions from his family that it would be safer not to.
Another shopper, who gave her name as Donna, said: "I looked for a security guard here, but I don't feel anxious. I feel quite resolute. Next week I'm going to a Hyper Cacher branch.
"You can't hide, you have to keep going. I feel okay. I'm more worried about not finding the things on my shopping list."
In the Yarden store in Golders Green, a cashier called Daniella said she felt scared, but that she would not let her concerns affect her life.
She said: "Yesterday people were asking me questions - how do you feel, are you scared? And then they say, 'but it'll never happen here'.
"It could happen anywhere. It is scary, because you would never think a week ago that it would happen in Paris, and then it did and suddenly it's real.
"I work in a kosher supermarket, it could have been me. But you just have to keep going. You can't be one of those people who doesn't ride the Tube because there was an attack once."
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