Rabbis, archbishops and assorted clergy decorated cakes, made mince pies and organised the winter stores for homeless charity Providence Row, as a follow-up to last month's Mitzvah Day.
Archbishop of Canterbury Rowan Williams, as well as the heads of the Reform, Liberal, Spanish and Portuguese and Masorti Jewish movements, volunteered at the Tower Hamlets charity following a meeting of the Council of Christians and Jews.
Others present included CCJ chief executive David Gifford and British head of the Catholic church, Archbishop Vincent Nichols.
Sixth formers from City of London Girls' and Boys' schools also helped out delivering dry goods they collected for the charity as part of Mitzvah Day.
Mixing cupcake icing for the opening of Providence Row's new building, Archbishop Williams said: "It is important to be here, doing something for others."
Mitzvah Day director Laura Marks, who received the Big Society award from Prime Minister David Cameron at Downing Street this week, said: "We want to start a long relationship between the school and the charity."
Reform president Rabbi Tony Bayfield helped to tidy the stock-room, full of donated tins, rice and pasta. He said: "It was good to come here with the CCJ, We have common values we agree on, that we serve God by helping others."
Year 13 pupil Joe Gamse said: "The school's Christian and Jewish societies collected food as a joint initiative. Coming here is important as it's easy to forget how much of an impact you can have."
Pam Orchard, chief executive of Providence Row, said the work done by the visitors had been "really useful work. But it also gives a flavour of the sort of things we do with our clients."
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