There was a full house at Belmont Synagogue on Shabbat for the induction of Rabbi Elchonon Feldman by the Chief Rabbi in the presence of a number of civic dignitaries.
Paying tribute to Rabbi Feldman, Lord Sacks said Belmont "could not have found a more outstanding individual to lead the community".
After the service, 350 people attended a lunch in the rabbi's honour, among them his parents and grandmother, who had flown over from America.
The rabbi said he and his wife Jacqueline were "very proud to be part of this community. Our future together could not be brighter." A native New Yorker, Rabbi Feldman came to Belmont from Israel with the London-born Jacqueline and their three young children.
The couple have run camps in the US, UK and Israel for young people with special needs and the rabbi taught Orthodox teenagers on a post-high school programme in Jerusalem.
He is the sixth rabbi of the 800-strong Belmont community since its establishment in the 1960s.