Last month in Berlin, Rabbi "Willy" Wolff attended a packed-out screening of a documentary - about himself.

He was so excited about the event that the sprightly 89-year-old shot up the steps to the cinema at high speed. "He overtook me on the stairs," said one of the event's hosts, Knut Elstermann.

The enthusiasm appears to be mutual: Rabbi Wolff - A Gentleman before the Lord is filling up arthouse cinemas across Germany, with over 10,000 people having seen the film so far.

The zip, energy and charisma of the liberal rabbi, whose family escaped from pre-Nazi Germany to the UK, are among the reasons for the documentary's popularity.

Rabbi Wolff, who speaks fluent German and previously worked as a European correspondent for Reuters and the Daily Mirror, was most recently the rabbi of the federal state Mecklenburg-Vorpommern, based in Schwerin, following stints ministering shuls in Newcastle, Milton Keynes, Brighton and Wimbledon.

The film follows the rabbi as he works at home in Henley-on-Thames, talks to other rabbis in Berlin, meets his Orthodox relatives in Jerusalem and floats in the Dead Sea.

His fearless sense of humour, evident throughout the film, was on display at the screening, where he was asked how he came to be the most renowned rabbi in Germany. He sparked laughter by replying: "I don't know if this makes me popular among my colleagues."

It was Rabbi Wolff's honesty that audience member Klaus-Dieter Ehmke appreciated most. He added: "He is an appealing figure and, in certain intellectual German circles, it's in vogue to be acquainted with such a Jew."

A British relative of the rabbi, Elsa Hillman, who travelled to Berlin for the screening, was not surprised by his popularity: "He is charismatic and very approachable," she said.

She was convinced that the documentary could succeed in "certain areas of London" such as Golders Green and Stamford Hill, "and not only among Jews".

Jürgen Pohl, director of Salzgeber, which distributes the documentary, said Rabbi Wolff was being shown in 21 cinemas nationwide, and six in Berlin. "This is very rare for a documentary," he said.

He added that director Britta Wauer's previous documentary about the largest Jewish cemetery in Berlin, In Heaven, Underground, had featured Rabbi Wolff. The rabbi, he said, turned out to be the "most beloved" figure in the film, which ran for a whole year, in cinemas nationwide.

Nora Pester, the publisher of Ms Wauer's book about the rabbi, Rabbi Wolff and the Things of Life, which includes interviews with him, said: "This film tells an off-beat Jewish story, which doesn't focus on the past. This is Jewish light."