The United Synagogue's largest congregation, Borehamwood and Elstree, will be without its senior minister on Rosh Hashanah.
Rabbi Chaim Kanterovitz underwent emergency surgery after being taken ill on holiday in Italy. Back in Hertfordshire, he was admitted to hospital after experiencing complications.
To fill the breach, the community has brought in Rabbi Yisroel Fine, who led Cockfosters and North Southgate Synagogue for more than 25 years, retiring at the beginning of 2014.
Recruited on account of his experience in leading a substantial community, he will be overseeing Borehamwood's rabbinic team - assistant minister Rabbi Baruch Boudilovsky, part-time Rabbi Yaacov Finn and youth minister Rabbi Amos Azizoff.
They will jointly preside over the three adult services at the shul's Croxdale Road site, where close on 1,500 worshippers are expected, and the 600-strong minyan at nearby Yavneh College. There are also youth and children's services.
"To have to find a suitable replacement rabbi for a community of our size with a week's notice has been exceptional," said Borehamwood chair Anne Gordon. "Our primary concern is for Rabbi Kanterovitz's health.
"We will miss him over Yomtov but we are very fortunate that Rabbi Fine and his wife were prepared to change their plans in order to join us at BES. We wish Rabbi Kanterovitz a full and speedy recovery."
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