Rabbi Kagedan proudly stands at the Walnut Street Synagogue bimah.

Unbeknown to the ten Chelsea families who founded the Orthodox Congregation Agudath Shalom in 1897, they had erected their synagogue in a city that in their lifetimes would become home to the largest percentage of Jews of any other city in the United States except New York.

In 1890, 82 Jews lived in Chelsea; by 1910, that number swelled to 11,000, one of every three residents. By 1930, almost half of Chelsea was Jewish, earning it the moniker, “Yerushalayim d’America.” If it seemed like there was a synagogue on almost every corner, that’s because there was: in its 1.8 square miles, Chelsea housed 18 synagogues.

When tragedy struck and the Great Chelsea Fire of 1908 reduced most of the city, including Agudath Shalom, to ashes, the shul’s immigrant founders were undaunted. They rolled up their sleeves and in 1909 rebuilt the synagogue on Walnut Street, which inspired the new building’s nickname, the Walnut Street Shul.

Designed by architect Harry Justin Joll, the magnificent building boasts ceiling frescoes painted by immigrant artists and an awe-inspiring ark by Sam Katz, the renowned master woodworker from the Ukraine who made Chelsea his home in the 1920’s.

Fast forward to 2017, and most everything about Chelsea has changed.

Gone are the kosher butchers, bakeries and religious and cultural institutions. Yiddish and Hebrew have been replaced by the mother tongues of recent immigrants from Central America, Asia, Southeast Asia and the Caribbean. According to the most recent Cohen Center for Modern Jewish Studies survey, Chelsea’s Jewish population has shrunk to statistical insignificance.

Of the 18 synagogues, two remain: Temple Emmanuel and the Walnut Street Synagogue.

The Walnut Street Synagogues’s congregants are determined to revitalize their synagogue and, while they’re at it, to blaze a new trail for Orthodox Judaism. Last September, they hired Rabbi Lila Kagedan, the first female clergy member in the United States to preside in an Orthodox synagogue using the title “Rabbi.”

Within the world of Orthodox Jewry, this is a big deal.

Rabbi Kagedan attended Yeshivat Maharat, the Orthodox women’s religious training program founded by Rabbi Avi Weiss in the Bronx, New York. Because rabbi is a masculine word, Rabbi Weiss allows his graduates to adopt whatever title they want.

Some choose rabba (a feminized version of rabbi) or maharat (a Hebrew acronym Rabbi Weiss invented that translates as female leader in Torah, spirituality and religious law). When Rabbi Kagedan and her two female classmates graduated in 2015, she alone chose the title rabbi.

“It was the title that most accurately described the work that I trained to do. Like calling a doctor ‘Doctor,’” she said. “People did try to discourage me because it hasn’t been a typical choice in Orthodoxy, but I always wanted to serve the community and use my training and knowledge to support the Jewish community with pastoral and halachik needs.”

The Rabbinical Council of America (RCA), which represents over a thousand Orthodox rabbis across the United States, saw the matter differently. It adopted a policy in the fall after Rabbi Kagedan’s graduation prohibiting the ordination or hiring of women rabbis.

“Should it be allowed? Who’s going to make it illegal?” asked Jonathan Sarna, the prominent author, historian and Brandeis University professor who has written extensively about American Judaism. “In America, the congregants make their own decisions. We don’t have a Chief Rabbi. We don’t have a Ministry of Religion. Every congregation is, in a sense, a law unto itself,” he said by phone from Jerusalem.

None of these religious politics mattered to Board Secretary Richard Zabot, whose grandparents arrived in Chelsea in 1905 from Russia and helped found the Walnut Street Synagogue. In Rabbi Kagedan, he saw a perfect fit. “She showed a willingness to work with the unknown in order to achieve our goal: the rejuvenation of our synagogue,” he said.

Fellow Board member Eddie Medros, who grew up in Chelsea in the 1950s and attended the Elm Street Synagogue, agrees. “She is infectious with her drive and enthusiasm. She brings warmth, passion, inclusiveness and a love of Judaism,” he said, noting she has already reached out to the local community in a meaningful way.

The attraction was mutual. “The shul presents a challenge, which I am always up for. I also feel committed to keeping a shul that has existed for so many years going. Continuity is powerful,” she said.

Devra Zabot, Richard’s daughter and events chair of the shul’s museum, described the extensive vetting process Rabbi Kagedan received before the synagogue board offered the ultimate vote of confidence. “Given that the board members are all over the age of 70 and mostly male, this was a heavily discussed decision,” she said.

In the ten months she has been at the spiritual helm, Rabbi Kagedan has been busy learning the ropes and making connections with the greater Jewish and local Chelsea communities. Almost immediately upon arrival, she led the High Holiday services and organized a Chanukah celebration with a klezmer band that attracted over 150 people, including Zahava Stern, a new young member.

“I met a lot of people who grew up in Chelsea and were bar or bat mitzvah-ed in this shul, but have since moved out to Sharon or Brookline. They were so excited to come back and see an active community in a place they hold so dear to their heart,” she said.

Stern also noted that Chelsea’s location attracts families from the North Shore, East Boston, Cambridge and Somerville. “It’s a secret gem right in the middle of the action,” she said.

The Walnut Street Synagogue offers monthly Shabbat and holiday services, classes on a variety of Jewish topics and holidays, and pastoral counseling and services. Rabbi Kagedan is the founding member of the Chelsea Interfaith Council and has met with the City Manager and other non-profit organizations about partnerships and integrating the shul with the Chelsea community.

The shul is supported by its board and members and by the Chelsea community at large, including citizens, city councilors and non-profit organizations. There are 120 members, and it operates as a fully Orthodox shul, with a mechitza on Shabbat and during high holidays services. The Jewish Chelsea Home generously opens its doors to the Rabbi and her family and guests to stay over on Shabbat.

Somehow, Rabbi Kagedan also finds time to serve on several professional and religious boards. “My peers have been largely supportive and open. Once people meet me and get to know me and see or experience the work I am doing, there is less anxiety and hype about being a woman Orthodox rabbi and people see me as just simply an Orthodox rabbi,” she said.

For now, Chelsea and the Walnut Street Synagogue are her prime focus. “Chelsea was at one time a real center of Jewish life in the region. My priority is to get Chelsea back on the radar of Jews in Massachusetts and to let people know the Walnut Street Synagogue is operational,” she said.

This is music to Richard Zabot’s ears. He remembers as a child when all 1,109 seats would be occupied during the High Holidays. “The shul hasn’t lost any of its charm or awe. We’re inviting 900 new people to join us this Yom Tov and be part of the preservation of the future,” he said.