They offered shelter, as befitting their lyrical name, and much more.

When members of an Orthodox congregation in Roslyn, L.I., lost their building earlier this year, they asked to rent space in the Conservative synagogue across town. The leadership of the Shelter Rock Jewish Center told them they could have it for free — but they added a condition, hoping it wouldn’t be a deal breaker: only if the Orthodox congregants joined.

Nearly all did.

“We never asked them for their assets; it was not a merger,” stressed Steve Goldstein, Shelter Rock’s vice president. “We simply offered them the possibility of membership and to incorporate them into our community. … Hopefully we will learn from each other.”

As synagogues around the country merge to cut costs, deal with flagging memberships and struggle to stay relevant in a fast-changing Jewish demographic landscape, the Roslyn situation is one of the more unusual such stories, and not just because of Shelter Rock’s offer of free rent. The coming together is a homecoming of sorts.

One of those who joined from the Orthodox synagogue, Warren Brown, noted that he had originally been a member of Shelter Rock. He said the Orthodox congregation, North Hills Synagogue, was a break away from Shelter Rock about 10 years ago.

Members had been using a building formerly home to the Boy Scouts. Earlier this year the building was sold by its current owners and they had to leave in June. After that, the members — some 25 in all — began holding Shabbat services in their homes while they scoured the area looking for a place to relocate.

“We spoke to schools and a community center,” Brown recalled. “We had to keep within walking distance [of their former home], and the only thing that made sense was the Shelter Rock Jewish Center.

“So we asked to rent space and they said they wanted us to be part of the community — to become members — and that they would give us the full use of their classrooms.”

As it turned out, the Orthodox members — they are now known as the North Hills Minyan at the Shelter Rock Jewish Center — moved into the downstairs auditorium and held their first Shabbat service there the week before Rosh HaShanah. Twenty of the 25 members made the move to Shelter Rock.

They moved in their ark, two Torahs, their pulpit, tallism, siddurim and High Holy Day prayer books, as well as the bookcases in which to store them.

“We probably have a little more space here than we did there, and we can seat at least 100,” Brown said.

He said the Shelter Rock congregation, which has a membership of about 400 family units, is “really bending over backwards to help us make a smooth transition.”

As an incentive to get North Hills members to join, Shelter Rock offered them reduced membership for the first two years. Instead of paying the full $2,050, the first year’s dues are $1,250.

“We are trying hard to deal with them in a friendly way and to make them feel welcome,” said Rabbi Martin Cohen, Shelter Rock’s spiritual leader for the past 12 years. “Their initial emotion was one of unhappiness. They had had a synagogue and they were no longer independent, but we are trying to make them feel that some good can come out of it. They are joining a vibrant community that has things they didn’t have when they were on their own.”

For instance, he said, Shelter Rock has a caterer, a nursery school and a Hebrew school and a cantor.

“We’re a much bigger operation and we can do more,” Rabbi Cohen said. “I know they were devoted to their synagogue and felt insecure. We are trying to say that is over, that you are a part of a secure operation that is enduring, and that you can now concentrate on other things rather than just hoping the congregation doesn’t vanish over night.”

Goldstein noted that the synagogue’s caterer has OU glatt certification, and that “we are working out the Kiddush to make sure that what we do is going to make them comfortable.”

Thus, when members of the Orthodox group said they could not attend a congregational meal in the sukkah because a microphone was to be used, it was decided not to use a microphone.

Goldstein said he was gratified to see three Orthodox members at the recent synagogue barbecue.

“We’re committed to making this work,” he said.

Rabbi Cohen said that when Shelter Rock was founded in 1957, the neighborhood was 90 percent Jewish.

“Now it’s much less and we are trying to hold on and create something spiritually meaningful on a neighborhood level, making this a place for pre-school, elementary, high school and college students. One of the nice things is that we have both older and younger members. … We try to remove and not impose barriers on the sense of friendliness that should permeate the community.”

Although there were a few Orthodox families who paid dues to both congregations, Rabbi Cohen said there was no interaction between the two congregations.

“Even though we were less than a half-mile away, I met their former rabbi only once in our lobby when he came here for a simcha. We seemed to live in contiguous but impenetrable worlds.”

Rabbi Cohen observed that there were “some people who felt they [the Orthodox] should be punished for having left and now come back — that we should take pleasure in it. … Some thought I would take pleasure in the demise of an Orthodox synagogue — that I would take ghoulish glee in it. To even think that is not kind. I take no pleasure in the loss of that synagogue.

“At the end of the day, these are Jewish people who had no place to daven [pray] and we had the room to accommodate them. … It seems to be a success. We are trying to de-emphasize that we have two families under one roof. We are one family with a variation in the way we do things.”

Joy Perla, a Shelter Rock congregant since 1975, said she remembers the Orthodox minyan before it broke away. She said it was comprised of the children of members and that the loss of their building “is a wonderful opportunity for both North Hills and Shelter Rock. It’s a very good indication that there are Conservative shuls that are respectful and open to other Jews in the community who need a place to daven.”

She pointed out that after Shabbat services, the two groups come together for a joint Kiddush, “which is what we had 35 years ago.”

“It’s the same setup and it’s heartwarming to me that we were able to do it,” Perla said. “I’m proud of my congregation for doing this. I think it’s very positive. … We should be a big tent.”

United Synagogue of Conservative Judaism’s CEO, Rabbi Steven Wernick, agreed, using the same inclusiveness metaphor. “I think it’s wonderful,” he said of the merger. “Its a big tent. If it’s possible for synergy and mutual support, we should do that.”

Brown noted that about seven years ago there was a group of about 40 Sephardic families that broke away from North Hills Synagogue, leaving the Ashkenazi behind. They now meet in people’s homes and he said there is talk about them rejoining the North Hills minyan.

“There is some indication the groups may get back together,” he said. “We would be happy about that.”