It’s a few minutes before sundown, and Ruchama Burrell is in her Berkeley kitchen scrambling to finish the last few touches on the Shabbat meal she will soon serve. No matter if sundown is at 5:30 or 8 p.m., it’s always a sprint to the finish line, she says.

Mazel, a Chinese Shar-Pei, paces back and forth while guests make small talk in the book-filled living room; any offer of help is politely refused.

Ruchama’s husband, Avraham, who helped earlier with the cooking, is at services at Congregation Beth Israel, where the couple belongs. If it’s a typical Friday, he’ll bring home a new face — maybe several.

This scene repeats itself each week, as it has for the past 25 years.

Ever since Sarah and Abraham opened their tent to three strangers in the Genesis tale, Jewish tradition has considered it a great mitzvah to welcome guests into the home, particularly for Shabbat and holidays. Some might say the Berkeley couple takes that value of hospitality to the extreme.

“Their hosting is legendary at this point,” said Beth Israel’s Rabbi Yonatan Cohen. “Wherever I am, whether it’s Jerusalem or New York, when I say I’m from Beth Israel, someone says ‘I was at that couple’s house.’ ”

“Hosting guests is a mitzvah that you enjoy in this world, but you reap the blessings in both this world and in the world to come,” explained Ruchama.

The fact that the Burrells are always hosting guests — from 10 to 17 people on any given Friday — isn’t the only thing that makes their Shabbat table noteworthy.

Each week, they advance one letter in the alphabet, cooking a cuisine from a different country. If it’s B, it might be Bulgaria or Belgium. If it’s G, it might be Great Britain or Georgia (the one in Eurasia). If it’s I, it will most likely be Italy, as that’s one of Ruchama’s favorites. And given their diets, there will always be a vegan entrée along with the meat entrée (Ruchama is vegan).

It all started in 1990 when the couple, who met at a Chabad rabbi’s house in San Francisco, began hosting Shabbat dinners as newlyweds (Ruchama is on her fourth marriage and Avraham his third; they were in their 40s when they married). It was Avraham’s idea to serve food from a different country every week, but Ruchama worried that with so many to choose from, “we’ll go nuts,” to which her husband replied, “Let’s go by the alphabet.”

And so it began. In March, they celebrated a quarter-century of serving international kosher feasts at their Shabbat table.

After a few years of hosting dinners in San Francisco — including a particularly memorable Chinese meal when their back deck caught on fire — the Burrells moved to Berkeley in 1994 and quickly became part of the Beth Israel community. Avraham wears many hats there; he is not only a mashgiach (kosher supervisor), but it’s also his job to inspect the Berkeley eruv before Shabbat every week to ensure that the religious boundary circling the neighborhood is intact.

While the Burrells have their regulars, it’s not uncommon for their rabbi to call to find out if they have room at their table for guests visiting the synagogue.

“What happens at the shul needs to be extended to the Shabbat table,” said Cohen. “People get transformed not just in pews, but by seeing families observing a rich and observant life, and what happens around the Shabbat table is often the transformational feature. I think their home has been the first entry for many into observant life, in seeing how you have a Shabbat table and create a Shabbos atmosphere.”

Abigail Dembo, a grad student at U.C. Berkeley, is a good example. About five years ago, she saw a woman in a Safeway parking lot who had a similar breed of dog to her own. As the two exchanged information to make a doggie play date, the woman mentioned the Shabbat dinners. Dembo had attended Jewish day school, but at the time was completely disconnected from Judaism.

A few months later, she decided to go to one of the dinners at the Burrells’ home. “From the first time I went, I loved it,” she said. “There was something about the feel of that table where it was like, ‘Oh, this is what it’s supposed to be like, here it is.’ I feel weird saying it, but my heart opened. I was having this nagging feeling of trying to figure out where I would fit into the Jewish community as an adult.”

Dembo has been a regular now for over five years. Others come and go; a few grad students are always in the mix, while other guests are closer in age to their hosts. Occasionally the Burrells’ own children or grandchildren attend. “We love it when people are regulars,” said Ruchama. “Part of the whole thing about Shabbat … is you don’t have to make a date to see someone; you know they’ll just come. It creates a community once a week, and people get to know each other here in an informal kind of way.”

Over the 25 years, a few couples have gotten together at these Shabbat meals (the Burrells just attended the wedding of a couple who met at their table), while some have fallen apart, and others have taken a break while raising their children, and then returned.

“And some people come for awhile and then stop because they begin doing it themselves,” Ruchama said. That was the case for Ken Maki, who hosts weekly Shabbat dinners at his Oakland apartment for members of Beth Jacob Congregation. He said he was inspired by Ruchama and Avraham while attending Beth Israel with his late wife. In 2013, his hosting experience brought him together with Kathy Hollander, who earlier this year became his new wife (www.tinyurl.com/maki-hollander-unions).

Cohen said about the Burrells, “The fact that they’ve both been through personal journeys makes them particularly sensitive to issues that some people who frequent their table may experience. The fact that they’re so open with their stories makes others feel comfortable; an open heart invites an open heart.”

Ruchama was born Linda Madden, and Avraham was born Peter Burrell. Neither were born Jewish.

Ruchama grew up in a military family and spent her early years moving around the country. Her paternal grandmother had some Jewish ancestry, but her father “knew nothing about religion,” she said. Her mother was raised Southern Baptist and brought up Linda in the same faith.

Ruchama attended a Catholic university and sat with the Quakers for many years. By the time she reached San Francisco, she decided to investigate her Jewish heritage, “and it fit right away. It happened very fast,” she said. “When people ask why I converted, I tell them ‘I could give you a reason, but it wouldn’t be the truth, because you don’t know what happens with these things; you have no idea why. The Torah calls some people to herself.’ ”

Avraham is the fourth generation to be born in the Bay Area, and he believes he has some Jewish ancestry through a grandfather, as well. Raised in a devoutly Catholic family, he attended Catholic school until he rebelled in his teens. He was introduced to Judaism through his second wife and had a Reform conversion. After their divorce, he had an Orthodox conversion. Before retiring from the postal service, he was one of two religiously observant mail carriers in Northern California who refused to deliver mail on Saturdays, he said.

Avraham is even busier in retirement. He oversees U.C. Berkeley’s kosher sandwich-making operation, is the official mashgiach at the teen program Midrasha and the unofficial one at Beth Israel, and freelances for the Vaad Hakashrus of Northern California and several kosher caterers. And he still finds time to play bass and manage the Ferris Wheels, Berkeley Chabad Rabbi Yehuda Ferris’ band.

Noting that the biblical figure Saint Peter — Avraham’s birth name — was “keeper of the keys to heaven,” Avraham now carries a huge ring with keys and has codes to all of the places he oversees as mashgiach.

Ruchama, who practiced law for 30 years, also has kept busy in retirement. She’s loved to cook since she was young, though she said she learned how in “self-defense” because her mother’s cooking was “horrible.” Also, she said, she realized early on that she wasn’t going to get by on looks alone, so she’d better learn how to cook. “It worked. Boys came around because I always baked cakes, cookies and pies.”

She became a vegetarian when she moved to San Francisco, going vegan about a decade ago when she visited an Aryuvedic practitioner who determined it was the best diet for her. (The couple never eats dairy, and Avraham eats meat only on Friday nights.)

While Ruchama likes the food of Mediterranean countries, she noted that “anyone can do France, but not very many people serve Finnish food.” She’s also learned that nearly every cuisine has a popular dish with cucumbers.

The Burrells never repeat a menu, and they’ve taken some creative license and included the cuisine of regions that aspire to independence, like Quebec (because the only Q country is Qatar, whose food would be identical to that of Oman, according to Ruchama).

For the same reason they skip over a lot of African countries, whose cuisines are quite similar. “It’s hard to get recipes that have enough variety and not end up with African hotel food,” she said. “We sometimes do South Africa or Zanzibar, but that’s it.”

The only time they break from form and don’t follow the alphabet is on major Jewish holidays, or when one of them is traveling.

Ruchama has several bookcases of international cookbooks that she’s used over the years, but now she can easily look online to find new recipes.

The couple chooses the country on Sunday night, and on Monday Ruchama plans the menu. On Tuesday, she makes the shopping list, and on Wednesday morning, they shop together. That’s how they keep each other in check: Avraham doesn’t buy enough, Ruchama tends to overbuy. They do some prep work Thursday night, including whatever bread dough they’re making to match the cuisine — along with vegan challah, using butternut squash purée in place of the eggs — and if the vegan dish requires the meat substitute seitan, Ruchama makes it in her slow-cooker. On Friday they are both cooking most of the day, though Avraham has to go out to check on the eruv.

They always seem to have enough, even if they need to bring out the emergency cans of stuffed grape leaves. “I don’t think anyone has ever left hungry,” said Ruchama.

They recite the Shabbat blessings, but they don’t sing traditional songs because the table is open to people of diverse backgrounds — non-Jews are welcome, too — and many guests may not know them.

The Burrells also have a “no politics” rule for discussions at the table, which came about after a guest years ago made a particularly offensive comment about nonobservant Jews. Because they want everyone to feel relaxed at their table, the couple has extended the rule to any topic that makes a guest uncomfortable. If a grad student is asked when her dissertation will be finished, or a single person is asked why he isn’t in a relationship, they can simply say “politics” to end the line of questioning.

The Burrells host pretty much 52 weeks of the year, with only a few exceptions. One time when they hosted a Shabbat dinner at the shul, they learned that a guest had shown up to their empty house; they decided going forward that they would be home every week, or get another household to cover for them.

Rona Teitelman is their downstairs neighbor and another regular — and the one person whom Ruchama allows to assist in the kitchen.

“There are always interesting people, and when there are many regulars, it’s like a big family of people who don’t have their own family nearby,” Teitelman said. “As a working single mom, I used to feel guilty about not making my own Shabbat dinner.”

Teitelman recalled one night when Japan was the featured country, and Ruchama was hurriedly rolling sushi in the kitchen.

She got word that an observant guest from New York had asked if he could help. Ruchama’s reply was, “Unless he wants to roll sushi, forget it.” It turned out he was a sushi chef who led kosher sushi-making parties for Orthodox Jews in New York. They had never had such tightly rolled sushi, said Teitelman.

“They’re such interesting people and have no shortage of stories about any number of things in their lives, but they are so deeply generous of spirit, probably more than anyone I know, and I know a lot of generous people,” said Teitelman. “It’s so important to them that everyone should be able to have a place to go for a Shabbat meal. That level of openness is uncommon.”

“We have no idea how many guests we have had at our table, but we are grateful for each and every one and look forward to many more,” said Ruchama, who is being modest, considering that well over 10,000 people have walked through their doors.

“Some people make a fuss about ‘this must be expensive,’ ” she said. But hosting Shabbat meals has become a way of life for the couple, who figure the costs into their budget.

“We don’t take vacations. When our anniversary comes, we think maybe we’ll go somewhere, but when I start thinking about it, what we really want to be doing is this.”

A few recent menus

England: Vegan challah (made with butternut squash instead of egg); garden salad with vegan buttermilk dressing; roast chicken with cranberry stuffing; vegan “handle wakes” (a casserole using seitan in place of chicken, with prunes, lemons, breadcrumbs and gravy, served at room temperature); English potato salad; vegan chocolate cake

Italy: Crusty Italian bread; anti-pasti (vegetables, olives, vegan salami); insalata mista (mixed bitter greens with oil, lemon juice and garlic); classic Italian roast chicken; seitan osso bucco; vegan butternut squash risotto; vegan tiramisu

Libya: Homemade flatbread; salad Arabieh (tomatoes, cucumber, radishes and sweet peppers); spiced mixed olives; Libyan almond chicken; vegan butternut squash and chickpea stew; brown rice; date cookies

Persia: Homemade pita; fresh spring herb platter with radishes, olives and walnuts; Persian vegetable salad (cucumber, tomato, mint, green onion and radishes with lime dressing); chelo (Persian-style basmati rice) chicken with ground walnuts and pomegranate syrup; seitan with walnuts and pomegranate syrup; vegan Persian Love Cake (flavored with rose water)