Mordechi Rosenfeld knew the joke about Grindr would crush if it included a Holocaust survivor.

Sitting at a center table at Reserve Cut, an upscale kosher steakhouse in Manhattan, Mr. Rosenfeld was unpacking his performance earlier that evening at an outpost of the Comedy Cellar, the club where he has been performing stand-up for more than three decades.

He had been trying some new material, including an extended riff about a personal experience on that gay dating app. Years earlier, he had unwittingly corresponded with someone who had an unexpected interest in the bedroom: World War II. Specifically, the German military.

The man who he had been messaging showed up at his apartment door in Nazi uniform. At that exact moment, Mr. Rosenfeld’s neighbor, a Holocaust survivor with dementia, exited his own apartment for a nighttime jaunt. The situation was understandably awkward: Mr. Rosenfeld acted as his neighbor’s caregiver and was frequently called on to collect him from the lobby or a hallway.

“Excuse me,” the man said, “I must have walked into the wrong room.”

Then came the punchline, energetically delivered in Mr. Rosenfeld’s Long Island accent with ever-so-slight Israeli inflection: The neighbor never again wandered away after dark.

The room, dotted with men wearing black velvet yarmulkes and observant Jewish women in wigs, exploded in laughter. The joke was a little edgy for some, Mr. Rosenfeld acknowledged, but worked because it was deeply Jewish.

“What we were talking about was not, ‘They’re hooking up and having sex’ — it’s how a Jew sees it,” Mr. Rosenfeld said. “Many comedians are comedians that happen to be Jewish. I’m a Jewish comedian.”

For 30 years, being a Jewish comedian meant working comedy clubs and the synagogue circuit, making a living performing for Jewish organizations from Borough Park to South Florida. He developed a loyal following, fans who knew him by his nickname, Modi. But the markers of mainstream comic success eluded him.

Now, in the two years since the attacks of Oct. 7, which brought the war in Gaza and rising antisemitism around the world, Mr. Rosenfeld, 55, is packing theaters by the thousands from Las Vegas to Atlanta, and Paris to Tel Aviv.

It’s an anxious and divisive time for American Jews. It’s arguably a great moment to be Modi.

His bits and clips from his podcast are reposted by hundreds of thousands on social media. Plans are underway to tape a comedy special in December — his second — and for a show at Radio City Music Hall in April.

Alex Edelman, the award-winning comic who’s been a fan since childhood, described what he called Mr. Rosenfeld’s “renaissance” in reverential terms.

“I’ve seen him do comedy in Yiddish. I’ve seen him do comedy for Hasidic crowds and for crowds where there’s not a single Jew,” said Mr. Edelman, who owned a DVD of Mr. Rosenfeld’s stand-up routine as a modern Orthodox teenager. “There’s no one like him.”

Mr. Rosenfeld’s ability to blend the contours of his identity — or “bubble hop,” as he calls it — has been integral to his recent success. He mines his Judaism for material, cracking jokes about family trips to Israel and the cultural differences between Ashkenazi and Sephardic Jews — often with punchlines delivered in Hebrew and Yiddish. He ends many of his performances with a collective singing of “Hatikvah,” the Israeli national anthem.

But now, he also mines his marriage to Leo Veiga, a 33-year-old who was raised Catholic.

At a New York show, and on the road in Ohio later in the summer, he asked if anyone in the crowd wasn’t Jewish. Just a few hands shot up.

Mr. Rosenfeld knows that is his current audience. But he is trying to expand — to figure out how to reach a more natural Grindr-joke crowd, while keeping the deeply resonant Holocaust-survivor punchlines. He wants, as he puts it, the “Goyim, gays and theys.”

“I swear to you — and this is from my heart — I don’t see the world as Jewish and non-Jewish, gay or straight, thin or fat, Black or white,” he said. “I see people who buy tickets to my show, and people who don’t buy tickets for my show. That’s the only way I see the world.”

The question now is whether the bigger, more secular world — one where antisemitism and Israel are fraught topics — will embrace him back.

‘Moshiach Energy’

On a sunny morning, Mr. Rosenfeld stands in gym shorts and a T-shirt, filming himself on his sun porch. He takes out a yarmulke and puts it on, kisses the corners of his prayer shawl and takes out his tefillin — the leather boxes worn on the forehead and upper arm during weekday prayers — to embark on his morning routine, whispering Hebrew prayers into the camera.

When he posted the video to social media, he titled it “ASMR: putting on tefillin.”

It’s a routine ritual for Mr. Rosenfeld, who leads services at his modern Orthodox synagogue in the East Village, studied cantorial singing at a Hasidic yeshiva and keeps a kosher home. But it’s branded with a twist, as a way to capture all his audiences — the observant fans who pray with tefillin and secular viewers more familiar with ASMR videos online.

Mr. Rosenfeld sees comedy as a holy mission, he explained on a sunny Sunday afternoon sitting in his second home, in western Connecticut, which he bought last year.

At the pool in the manicured backyard, Mr. Veiga was entertaining a group comfortable socializing in Speedos. Inside, Mr. Rosenfeld was diving into Talmud, the millenniums-old collection of rabbinical discussion.

He recounted the story of two anshay b’dicha, or people of jokes, who are praised by the prophet Elijah for bringing joy. There was an element of the tale Mr. Rosenfeld never quite understood: Why, he wondered, did the ancient Jewish rabbis feature two comics rather than just a solo performer?

The answer came to him one night, when he was dancing shirtless at a techno rave on ketamine with his husband. The comic can’t be alone. The comic must work with others to heal rifts through laughter.

A second epiphany about his work came when Mr. Rosenfeld was reading a Torah portion in which God describes Jews as the “chosen people.”

“They weren’t chosen to be the strongest and the most powerful and the richest,” he said. “Jews were put on this earth to create healing energy.”

Those revelations became a personal mantra that guides his comedy: “Moshiach energy” — Messiah energy.

For Mr. Rosenfeld, the slogan reflects a Messianic idea inspired by the last leader of the Chabad-Lubavitch Orthodox movement, Rabbi Menachem Mendel Schneerson. Mr. Rosenfeld interprets it as a mandate to pour positive energy into the world to help bring the Messiah.

With his comedy, Mr. Rosenfeld tries to offer a break from the polarizing politics that consume many in his audience. Like some of his fans, his political views are complicated. He has concerns about the positions on Israel expressed by Zohran Mamdani, the Democratic nominee for mayor in New York City, but also about President Trump, although he said he liked what he sees as the president’s support of Israel.

But tackling the complexity of Israel and the United States is not his project, he said. “My show is a pause for laughter” amid everything else that’s going on, he said.

The son of Israelis who immigrated to the United States when he was a child, Mr. Rosenfeld discovered his faith as a teenager on Long Island.

His observance deepened during college at Boston University, where he spent much of his time studying at a Lubavitch center near campus. He improved his Yiddish, which he heard from his grandparents, and absorbed the rhythms of old comics like Shimon Dzigan and Israel Schumacher, a famous Yiddish comedy duo.

“I’m like, ‘Oh my God, the timing, the cadence, the words,’” he told Marc Maron in an interview on his “WTF” podcast. “It’s another level of comedy.”

After school and a stint at a yeshiva in New Jersey, Mr. Rosenfeld accepted a job as an investment banker where he was, according to his husband, a “personality hire.” Dyslexic and diagnosed with A.D.D., Mr. Rosenfeld struggled with the details of finance.

He was, however, great at imitating the secretaries in the office.

A friend persuaded him to try stand-up and Mr. Rosenfeld was hooked. He caught the tail end of the Catskills scene, began performing at the Comedy Cellar and worked clubs across the country. He called his rabbi for a blessing before every show.

“You hear comics that say they’re comics because of some sort of child trauma or adult trauma,” said Donny Moss, a friend who booked Mr. Rosenfeld’s first standup spot in 1993. “He just was a very funny person who knew it and had this gift and did the work.”

Mr. Rosenfeld unsuccessfully submitted sets with less overtly Jewish material to Comedy Central and late night shows. But he built enough of a following with events for synagogues, Jewish charities and other community groups to become a full-time comedian.

“You have no idea what a rough crowd is until you are in front of 1,200 Jews that have just been fed,” he said. “If you don’t get them in the first five to eight words, they just get up and go. ‘Yeah, that’s it. I heard enough. I’ll be in the lobby.’ My competition was the lobby. Jews love a lobby.”

He wasn’t out professionally. But, he also wasn’t in the closet. Friends knew he dated men, as did his family. Mostly, Mr. Rosenfeld said, he worked.

“When my voice was developing, it was developing into a Jewish voice, not a gay voice,” he said. “I was gay, but I was just gay in the fact that I was sleeping with men. It wasn’t my thing.

“I worked nonstop,” he continued. “Every night, two or three comedy shows. Every weekend, either the Catskills or whatever hired me. I was working. I didn’t have time to be gay.”

From the kitchen, Mr. Veiga offered a different take: “Modi is a high-functioning bisexual. That’s why it never came up.”

‘Orthodox Ellen DeGeneres’

For much of his career, Mr. Rosenfeld followed a simple principle: “Know your audience.”

In a literal sense, Mr. Rosenfeld prides himself on being “an audience’s comic,” tailoring his set for his crowds rather than the critics and comedy nerds. But the phrase is also a spiritual double-entendre, referring to an order inscribed above the Torah scrolls in many synagogues: “Know in Front Whom You Stand.”

“Am I standing in front of God? A hundred percent,” Mr. Rosenfeld said. “God is one. Oneness. So my audience and me, when we are laughing together, geez, that’s God.”

Word spread over the decades. Mr. Rosenfeld performed before former Vice President Mike Pence at a Republican Jewish Coalition meeting in Las Vegas, cracked jokes before groups of Hasidic men in Brooklyn and thousands of Jews at suburban synagogues.

He roasted Senator Joe Lieberman (“the spine of a Democrat, the principles of a Republican and the wrinkles of Jimmy Carter”) and the conservative commentator Ben Shapiro (“that little bar mitzvah boy they put on the talk shows to annoy the other guests”) at annual benefits hosted by Commentary magazine. (“I never thought I would hear, let alone laugh at, a ‘Hitler-Goebbels-Shabbat elevator’ joke,” Mr. Lieberman said later when he took the stage.)

Then 2020 rolled around and, during the pandemic, live shows ground to a halt. But the organizations that hired Mr. Rosenfeld still needed to keep their members and donors engaged.

“Everybody calls up, we need Zoom shows — the U.J.A., R.J.C., C.J.C., R.J.J., J.J.J., all the J’s — and I figured out how to do Zoom shows that I was great at,” he said of suddenly performing for thousands of Jews online.

Mr. Veiga, who became Mr. Rosenfeld’s manager, suggested posting some of the clips on social media. Mr. Rosenfeld developed characters that went viral: a windbag Israeli named “Nir, not far,” and Yoely, a Hasidic Jew who offered his take on secular television shows.

As pandemic restrictions were lifted, Mr. Veiga began producing live shows, negotiating with Hasidic leaders and synagogue presidents about fees, security and more esoteric issues like which rules must be followed to perform on holidays. His audiences wanted to see the person — and couple — behind the jokes on social media. The couple decided to officially reveal their marriage with an interview in Variety.

He saw his role as making people laugh, but now also welcoming gay people into the observant community, letting “people who are Jewish, who are gay, know that it’s OK.”

Mr. Edelman called him the “Orthodox Ellen DeGeneres” for his role opening up the observant community to L.G.B.T.Q. couples.

As he dined with his husband, at the kosher restaurant in Lower Manhattan after his set, Mr. Rosenfeld was repeatedly interrupted by fans asking for photos and autographs.

An Orthodox woman approached the table and said she had taken a party bus with her girlfriends to one of Mr. Rosenfeld’s shows on Long Island last year, leaving her husband and seven children home. It was “girls’ night,” she explained, fawning over not only Mr. Rosenfeld but Mr. Veiga, too.

“These people started with him on his comedic journey in the beginning,” said Rabbi Gavriel Bellino, Mr. Rosenfeld’s rabbi and close friend. “He can almost say anything at this point because the connection is so deep.”

The couple say his original, observant fans have stuck with him.They often address the couple as “Modi and his gay husband.”

“As if I’m not gay, but my husband is,” Mr. Rosenfeld said.

‘I Always Prayed for It’

On Oct. 7, 2023, Mr. Rosenfeld and Mr. Veiga were in Tel Aviv, wrapping up a tour over the Jewish holiday of Sukkot. After the Hamas-led attack on Israel, they caught the last flight to France. Three days later, at a show in Paris, he began a new tradition of ending his sets with the singing of “Hatikvah.” He walked offstage to a standing ovation.

Anti-Israel protests outside the theater prompted the French police to ask Mr. Rosenfeld to cancel his final booking in the theater. He obliged.

As anxiety among his fans mounted, Mr. Rosenfeld’s following grew. He sold thousands of tickets in London, New York, Sydney and Melbourne. He made appearances in Vienna, Berlin, Munich and Warsaw, as part of what Mr. Rosenfeld called a “reparations tour.” Those shows, too, were popular, once Mr. Veiga could assure the audience that they would hire private security for the venue, he said.

He released his first comedy special in April 2024, with the title “Know Your Audience.”

The new fame surprises even Mr. Rosenfeld, who attributes much of his success to his husband, whom, as he tells crowds, he met on the New York City subway in 2015.

“I always prayed for it: The goal was touring comedian and then it happened,” he said, adding, “I got a husband who all of a sudden took care of the business.”

Really Knowing Your Audience

Linda Shaw had never been to the Funny Bone, a comedy club tucked between a Legoland store and an Auntie Anne’s pretzels in an outdoor shopping mall in Columbus. But when Mr. Rosenfeld scheduled a show, she drove from her home in Cincinnati along with a pack of girlfriends and several of her cousins.

Ms. Shaw, 56, was raised as a conservative Jew, the daughter of two parents from Europe. She married a non-Jewish man but raised her daughters as Jews.

So much Jewish humor “puts a negative light on Jewish life, and being an observant Jew,” Ms. Shaw said. Then, there’s Mr. Rosenfeld.

“You have him, who does it in a way that you can laugh and embrace your Judaism,” she said.

Mr. Rosenfeld’s opening act, a Christian comic picked because he also plays “clean,” struggled to adapt his act to this particular audience. His biggest laugh came from a throwaway line, “How many people here go to church?”

Mr. Rosenfeld delivered a 90-minute set that included many of his recent greatest hits, material his fans say helps them feel seen by him at a moment when they feel lost in the wider world. There were jokes about the popular “mission trips” to Israel sponsored by American Jewish organizations and Israeli tour guides.

He described being in Israel on Oct. 7, hearing the air raid sirens and watching the pop singer Bruno Mars evacuate the hotel in a platoon of cars.

Even in that life-or-death moment, Mr. Rosenfeld knew his audience.

“I said, ‘Leo, thank God they got Bruno Mars out of there,’” he recounted. “I said, ‘If a bomb hits this whole place and me and Bruno Mars both die, I will get zero press.’”