Should men shave or wear beards? Is the Torah a book of divine laws or a set of moral suggestions? Should people of the same sex be allowed to marry?
Such questions have long sparked vigorous debate within Judaism, at times prompting divides between communities or branches.
But no such discord will prevail this week, if thousands of local Jews have anything to say about it.
On Friday, Jews of all denominations plan to join in a citywide celebration and observance of Shabbat — the Jewish Sabbath — and all that it means within Jewish history and culture.
Organizers describe the inaugural Baltimore Shabbat Project, the local iteration of an international movement, as an effort to bring Jewish people of all descriptions together around a tradition they all share, and in a spirit of affirmation.
"So often it's the negative things that bring us together," says Rabbi Nitzan Bergman, co-chairman of the board that planned the multisite event. "When Israel is in crisis, for example, we all say, 'Yeah, you're my brother.' But Shabbat is a uniformly recognized value. Jewish people may observe it in different ways, but it's always there. The goal is to unify our community around something positive."
The festival began Wednesday with an evening of Shabbat-themed magic and crafts for men and continued with a "Challah Bake" that ticket vendors predicted would attract more than 3,000 women to the Maryland State Fairgrounds in Timonium Thursday night.
More than 150 volunteer families will host Sabbath dinners for observant and nonobservant Jews in homes across Baltimore Friday night, and about 50 Jewish organizations — including Reform, Conservative and Orthodox congregations — will hold special Shabbat services, and serve Shabbat meals, on Saturday.
The event is to culminate with a Shabbat-ending Havdalah service and a free outdoor concert by Moshav, a Los Angeles-based rock band with Jewish roots, at the Baltimore Jewish Community Center in Owings Mills Saturday night.
One Jewish community leader unaffiliated with the effort applauds the idea.
"There's a lot of divisiveness within, and between, many strains of religion, Jewish or not," says Arthur C. Abramson, executive director of the Baltimore Jewish Council. "This is a way of bringing people together, and that helps one side understand where the other is coming from."
The Baltimore Shabbat Project has its roots in Johannesburg, South Africa, where Warren Goldstein, the country's chief rabbi, decided four years ago to challenge all the nation's Jewish people to keep the Sabbath — a 25-hour period of religious observance that begins every Friday night at sundown — one weekend in October of 2013.
Organizers used a hashtag, #KeepingItTogether, a Facebook page and the support of local celebrities to raise awareness. Bergman, a native of South Africa, says even the founder was surprised at the degree of interest.
More than 70 percent of the nation's 75,000 Jews observed elements of the day, which included a range of community events and Torah readings according to Orthodox guidelines.
Word spread via social media, celebrities such as Paula Abdul and Mayim Bialik talked up the event, and the following year, similar festivals erupted in 465 cities in 65 countries. Most were planned by grass-roots organizers, giving birth to what is now called the International Shabbat Project.
The U.S. cities included Miami, Cleveland and Chicago. In Baltimore, Bergman and a few others experimented last year by organizing a "Great Challah Bake" that drew more than 1,300 women to the Baltimore JCC to bake the braided bread traditionally served at Shabbat meals.
The turnout was so strong it inspired Bergman, an Orthodox rabbi, to go bigger this year. He and Liora Hill, a member of a local Reform synagogue, became local co-chairs, engaging 104 volunteers to serve on six committees and lining up corporate sponsors.
Each committee has Orthodox and non-Orthodox co-chairs.
The event represents the "whole spectrum of the [Jewish] community right from the top," Bergman says, and supporters took note.
"Last year was very successful as a pilot. So many different kinds of people attended. We're hoping it will bring out even more parts of the community this year," says Ruth Miller, community planning director for the Associated: Jewish Community Federation of Baltimore.
Shabbat has its origins in Genesis, the first book of the Torah, in which God is described creating the world in six days and resting on the seventh.
"Through the gift of Shabbat, the Torah has given us a framework for our week," writes Rebbetzin Gina Goldstein, Warren Goldstein's wife, in a guide the International Shabbat Project has made available to local leaders this year. "We are to use our creative energies for six days and then dedicate one day for developing our spiritual and emotional energies by refraining from work
Just what form that takes can vary widely, depending on the denomination, the community, the family and the individual.
The laws governing the observance of Shabbat are so complex that rabbis can study them for years, but they center on banning the 39 forms of labor in which the Book of Exodus showed Israelites taking part as they built the tabernacle, the portable worship space they employed while in exile.
The most conservative Orthodox Jews interpret that as prohibiting most activities that can even remotely be construed as falling under those headings, from driving, cooking and using computers to smoking, shopping, wearing makeup or taking a hot shower.
Others, from Modern Orthodox on the conservative end to Reconstructionists on the other, might eschew some rules while choosing from among the many other traditions that have evolved, including the lighting of kiddush candles and the reciting of blessings on Friday night, the serving of three festive meals during the period and the singing of traditional songs.
Not all Jews observe Shabbat — many who consider themselves Jewish by culture but not religion do not, according to a 2013 Pew Research Center survey on Jewish life in the United States — but Bergman believes Jewish people of all stripes still esteem the occasion.
That makes it the ideal tradition around which to rally, he says.
"I don't think there's any Jew that would say 'you can take Shabbat out of Judaism,'" he says. At times "we've taken God out; we've taken the Bible out. But somehow, Shabbat is essential, mostly, to all Jews."
In his view, an enterprise like the Shabbat Project might have been impossible as recently as 20 years ago, so sharp were the disagreements across denominations.
Some scholars agree.
Gary Zola, a professor of the American Jewish Experience at Hebrew Union College – Jewish Institute of Religion in Cincinnati, says the Orthodox have grown so rapidly in number and vitality that fewer find themselves bristling at the notion of compromise with members of the more liberal branches.
The Orthodox population has grown from about 7 percent of American Jewry to 10 percent over the last ten years, Pew found, and its demographics skew much younger.
Membership declines among non-Orthodox congregations have also stirred a yearning for traditional rituals, Zola says, establishing more areas of common interest between the two.
"Denominationalism in America is in no way passe, but denominations that once existed in silos, socially and culturally separate from each other, are now definitely intermingling more," Zola says.
At the Rosenbloom Jewish Community Center in Owings Mills on Wednesday, boys and men watched a Shabbat-themed magic show and worked with an Israeli artist, Avi Zukerman, to create a personalized yad, a pointer used while reading the Torah.
Organizers say the observant and nonobservant alike are welcome to attend events such as the Friday night dinners, where hosts have invited members of disparate groups and are expected to lead open-ended discussions on the meaning of Shabbat in modern life.
The Suburban Orthodox Congregation is set to cohost a Shabbat dinner with the area's largest Reform synagogue, the Baltimore Hebrew Congregation, a joint event between communities whose members might otherwise find themselves at odds over fine or not-so-fine points of theology or practice.
At just about the same time, more than a million Jews are expected to be keeping Shabbat in one way or another in more than 550 cities and 65 countries worldwide.
To Zola, that can only be a good thing.
"It's wonderful that the Orthodox and more liberal [Jewish] communities are involved and supporting this," he says. "That shows there's something there for everybody. That's a winning thing."