In Cuba, the Jewish community was more than 15,000 strong when the 1959 revolution brought Fidel Castro to power, but before long it was decimated by an exodus that took most of its wealthiest members.

Now, only a handful of young people in the island nation are interested in Judaism, and many of the remaining 1,200 Jews are growing old.

Luis Chanivecky, a composer of jazz and classical music, is one of many who left Eastern Europe in the 1920s and 1930s, including some, prevented by quotas from entering the United States, who had hoped for a brief stay.

But many settled and thrived, and by the mid-1950s, the community had five synagogues including an extravagant community center, The Grand Synagogue of the Hebrew Community.

But within three years of the revolution, 90 percent of the Cuban Jewish population was in the United States, and now, like the community, the synagogue is divided.

As membership dwindled, officials of the Conservative (traditional, but not Orthodox) synagogue agreed to rent and finally to sell half the building to the Ministry of Culture, according to Adela Dworin, the synagogue's general secretary.

"The terms were very favorable to us. With the money they are paying we can maintain this community for 20 years more," Dworin said. "The government could have said 'We need the whole building,' and confiscated it."

As she spoke, rock music drifted through the building's library, offices, and banquet hall. A theater troupe was rehearsing a Bertolt Brecht production.

With 200 active members, the Grand Synagogue is the largest Cuban synagogue, but fewer than 25 of those members regularly attend Sabbath services. Upstairs, the large tabernacle, with room for 2,000, is unused, rain dripping through windows broken by rocks from grade-school students next door.

Government officials promised to provide materials for repair to the community's portion of the building when the ministry's side is repaired. For now, the water continues to drip into the tabernacle.

Cuban Jews assure visitors -- both on and off the record -- that the government treats them fairly, even granting them some privileges.

For example, meat, a rationed commodity, is available in the state stores with the same interminable lines afflicting much of Cuban life. But Jews can use their ration cards for ritually slaughtered meat from the country's one kosher butcher, "and there's no line," said one man, with satisfaction.

Cuban Jews live in an odd twilight, at peace with the government whose very existence undercut their numbers and strength.

The Marxist government tolerates and even grants favors to the Jewish community while teaching its children to believe in a godless world. Five full-time Jewish schools -- like all private schools -- were nationalized, yet no restrictions on religious practice were imposed.

"There's no tradition of anti-Semitism in this country," said Chanivecky, who is treasurer of the Grand Synagogue. "There have been no Jewish persecutions."

Downstairs, Sabbath services are still held in a small chapel where one of the congregation must lead worship. There is no rabbi in Cuba.

In the wooden pews one hot morning were a dozen men, most over 60, a teen-ager, a young boy and a girl. The air was stale and still. A frail man of about 70 walked to the altar and began a traditional Hebrew chant. Few others bothered to look at battered prayer books, printed in New York, but their voices rose and fell in the rhythmic murmur of prayer.

While religion is permitted, Zionism is not. Cuba has consistently sided against Israel, supporting the 1976 U.N. resolution calling Zionism a form of racism.

"Sometimes it's silly," Dworin said. "Saudia Arabia, what kind of progressive country is this? You can find more socialism in Israel. Maybe someday, if Israel improves relations with the Soviet Union, there will be a change in policy and relations with Cuba will improve, too."

And while no stigma is attached to Judaism, congregation members say they think ambitious Communist Party members would not practice the faith.

Canadian Jews are spoken of warmly and U.S. Jews with a touch of bitterness. From the Canadian Jewish Congress has come ritual food for Passover: meat, matzoh, wine. From the closer and richer United States has come nothing except some recent "propaganda," Dworin said.

"We need more books, more recently published books," Dworin said. "Most of the books here were published before 1960. Of course, some books will never be old, like Sholom Aleichem, or Shalom Ash. But we wonder, what's going on in Jewish literature in other countries?"

Those books are one way for a new generation to find its heritage, and the community's elders look to anything they can to cultivate that interest.

"Los nin os, the children, they don't come much," said 76-year-old Lazzarro Bennado.

"The younger people are not interested in religion," Dworin said. "It is very difficult in a country raised on materialism. There's no place for God. But not only the synagogues are empty. The churches, too."

Recent efforts have produced a group of 20 teen-agers who listen to music and dance at the synagogue Saturday nights. A Mexican rabbi sent a videocassette player that helped attendance.

"We are getting old," Chanivecky said. "In the future they will be our substitutes. It is up to them to keep alive our flame."