On the evening of June 15, the Jewish Center of Teaneck held its first gala dinner in more than a decade. It was celebrating two milestones, one global and one local: the 50th anniversary of the reunification of Jerusalem and the revitalization of the synagogue.

JCOT was built in 1933, at a time when a gentile had to front the real-estate transaction for the small group of founders because Jews were not allowed to buy property in the township’s former Phelps estate. The congregation hit its stride in the 1950s and 1960s as membership rolls swelled to around 1,300.

When its current rabbi, 32-year-old Teaneck native Daniel Fridman, took up his post in September 2016, the number of members had shrunk to 77.

In the intervening years, external and internal upheavals took their toll. The synagogue was neither evolving along with the Conservative movement nor adapting to the fast-growing Orthodox landscape surrounding it.

Originally affiliated with the Conservative movement’s United Synagogue of America, JCOT chose to take an independent path in the 1970s as a “traditional” shul led by Orthodox-ordained rabbis. The genders weren’t separated for prayer, but women could not lead prayers or be counted in the minyan. Meanwhile, Teaneck’s Orthodox community began flourishing and JCOT members who leaned in that direction suddenly had many other shuls from which to choose.

Eva Lynn Gans, a JCOT member since 1950, remembers when the main and auxiliary sanctuaries were overflowing on the high holidays. By the time she became the shul’s first woman president, in 2010, the annual fundraising dinner-dances that had been wildly successful in past years had been discontinued for lack of members.

“As the years went by, the Conservative movement in general lost members,” Ms. Gans said. “Our center never went egalitarian, and the people who wanted that left. Others died or moved away. And we were struggling. I saw that the only way to survive was to go Orthodox.

“I managed to convince two-thirds of the membership to have an Orthodox service and that was step 1.”

In March 2013, the Jewish Center of Teaneck became a member of the Orthodox Union and a few new members joined. But that growth was not nearly enough to sustain the massive building. Its 60,000 square feet of usable space includes banqueting facilities, classrooms, an indoor swimming pool, and a gym.

It was clear that the only solution was to sell the building, but that presented all sorts of problems. Isaac Student, the shul’s outgoing president, “brilliantly managed to convince the board and membership to sell,” Ms. Gans said. “Without Isaac, we would have run out of money.”

The sale to a boys’ yeshiva high school, Heichal Hatorah, was finalized in June 2016, in an agreement that grants the congregation permanent use of the building. Other organizations rent space in it, including Yachad — The National Jewish Council for Disabilities; Sinai Schools, which established a high school program at Heichal Hatorah; and Shalom Yeladim preschool, where Rabbi Fridman and his wife, Chaya, send their daughter, Eliana.

The infusion of funds enabled the JCOT board to hire a new rabbi. The previous spiritual leader, Rabbi Larry Zierler, served from 2006 to 2014 and oversaw the transition to Orthodoxy. “He was wonderful, but he saw we couldn’t afford him anymore so he stepped down,” Ms. Gans said.

After the sale went through, “We were lucky to get Rabbi Fridman, an amazing speaker and teacher who has attracted new members,” she added.

Membership now stands at 110 units — individuals and families.

In the two unsteady years that followed Rabbi Zierler’s departure, JCOT ritual director Yitz Cohen, as a volunteer, had filled some of the roles of a shul rabbi. Isaac Student’s wife, Nechama, “managed to have a kiddush for us every week,” Ms. Gans said. The Students and Mr. Cohen were the three honorees at the June 15 dinner.

“To say that we would not, as a congregation, be where we are today without the Students is an understatement of enormous proportions,” Rabbi Fridman wrote in a letter to congregants, adding that Mr. Cohen “played a crucial role in stabilizing the congregation during challenging times over the last number of years.”

The young rabbi said that when he was hired, “the shul had already become fully Orthodox and it was my job to revitalize the place. Incredibly dedicated lay people worked with me to really make it a dynamic modern Orthodox shul that everybody could feel comfortable in, irrespective of educational background or observance level.”

Today, JCOT offers three daily minyanim and adult-education classes on Shabbat and Monday nights. The sisterhood came back to life after lying dormant for 15 years. Rabbi Yishai and Yiskah Klein, Israeli emissaries teaching at Ben Porat Yosef in Paramus, recently were hired as fulltime youth directors. Rabbi Klein leads a new Shabbat youth minyan for third- to fifth-graders. A knitting group and a book club also meet at the center during the week.

“Now, instead of board reports on how many members have quit or died, we get reports on new members,” Ms. Gans said. “It’s just been great.

“A lot of people have become regular attendees, including some of the old-timers who stuck it out. Some of those who left us when we went Orthodox have come back. It’s really the place to be right now.”

“This uptick is very gratifying to me,” said Mr. Student, who has been a JCOT member for 40 years. “The last three years have been very challenging — and that is an understatement. But we have pulled through, thank God, and I am very optimistic. We now have children running around on Shabbat, and the building is full of Jewish activities. We have a wonderful rabbi who has taken an aggressive lead to revive the center. It’s almost a rebirth of the Jewish Center, and this is just the beginning.”

It was Rabbi Fridman’s idea to relaunch the annual gala dinner and to tie it in with celebrating the reunification of Jerusalem in the wake of the 1967 Six-Day War.

“It is altogether fitting and appropriate that we should celebrate our communal and national restoration in conjunction with one another, as we must always be cognizant of the fact that our synagogue, amongst synagogues all across the diaspora, represents a stone in the edifice of a fully rebuilt Jerusalem,” he explained to congregants.

Anchoring JCOT in Israel and Jerusalem is a big part of the educational message he seeks to instill, he added.

Rabbi Fridman graduated from Yavneh Academy and the Frisch School in Paramus, and then studied for a year at Yeshivat Har Etzion in Israel before receiving his B.A. in biological sciences from Columbia University and ordination at Yeshiva University’s Rabbi Isaac Elchanan Theological Seminary. He now also is an administrator and teacher at Torah Academy of Bergen County. His wife, the former Chaya Gopin, also a Teaneck native, is a neuropsychologist.

Chaired by Lori Rosner, the gala dinner included a “siyyum mishnayot,” a ceremony marking the completion of the study of a book of the Mishnah, led by Dr. Jonathan Resnick. “The dinner was, thank God, very successful at multiple levels, in terms of our being able to express gratitude to the Almighty for a reunified Jerusalem, in terms of our being able to thank those who have served us so faithfully, in terms of our ability to make a siyyum reflecting our commitment to Torah, and in financial terms as well,” Rabbi Fridman said.

“But the sum was much greater than even these important parts,” he continued. “As Zechariah once said, ‘Not with the army, and not with force, but with the spirit, so said the Lord,’ this dinner was about the indomitable spirit of a community that has weathered the storm, and, with the help of God, looks forward to a future bright enough to match, and exceed, an august history of 84 years.”