Nearly 10 years after they rebelled against their communist rulers and broke down the Berlin Wall, eastern Germans are waging a different kind of grass-roots revolution that may soon shatter a hallowed national tradition: the ban on Sunday shopping.

In a country that takes its leisure time very seriously, Sunday has always been sacrosanct and is even enshrined in the German constitution as "a day for spiritual reflection." But for many eastern Germans, who grew up in a largely atheistic culture, the western law that attempts to keep Sunday free of material trappings is seen as an infringement on their freedom.

Two months ago, a consumer rebellion took root in the eastern city of Leipzig--where candlelight protest marches in the fall of 1989 foreshadowed the demise of the German Democratic Republic and the reunification of the two Germanys the following year. Fed up with shopping strictures that cramped economic growth in a region where one out of five people are out of work, Leipzig Mayor Holger Tschense decided the time had come for drastic measures.

Taking advantage of a legal exemption that allows railway stations to sell goods on Sunday, he transformed the sprawling terminal into a multilevel mall that he touted as "a shopping paradise for all of Germany." Then Tschense went one step further and declared the entire downtown area a tourist zone--which exploited another loophole that allows shops catering to tourists to remain open on Sunday.

Before long, Leipzig's ploys were being adopted in Dresden, Halle and other eastern cities where consumers were clamoring for the right to shop till they drop. In recent weeks, the trend has spread to Berlin, where large department stores have opened their doors on Sunday to tens of thousands of shoppers by saying their wares--from vacuum cleaners to nylon stockings--should be considered items of touristic interest.

At the Kaufhof department store on Berlin's central Alexanderplatz, where store managers estimate that up to 80,000 people are now coming to shop on Sundays, small round stickers depicting the Brandenburg Gate and saying "Berlin souvenir" were affixed to all products sold.

When city authorities sought to impose a $27,000 fine, Kaufhof agreed to abide by the law but exploited another legal loophole that approves Sunday shopping if it is necessary to accompany special events. So Kaufhof now stages festivals each Sunday, featuring bands, clowns and juggling acts, to justify its Sunday opening.

"We're only giving the people what they want," said Guenter Biere, Kaufhof's managing director. "There are taxi drivers and nurses who work on Sunday, so why can't people shop? It's really intolerable that politicians seem to be the last to know what is important in serving the people."

Ottmar Schreiner, party manager for the ruling Social Democrats, warns that the government cannot allow the department stores to continue "playing tricks" to stay open on Sunday. "What they are doing will eventually lead to the erosion of public respect for the authority of law, and we cannot allow that to happen," Schreiner said.

The department stores have been urging German legislators to loosen the restrictions. But it took parliament more than a decade to finally agree to allow stores to extend their hours until 8 p.m. on weekdays and 4 p.m. on Saturdays--a delay that reflects the glacial pace of reform in Germany.

Any change in the Sunday ban would encounter opposition from such powerful institutions as churches and labor unions. Bishops and priests insist the clause in the country's 1949 constitution requiring respect for the Christian Sabbath is a cornerstone of German cultural heritage that must be respected. Labor leaders say that allowing stores to remain open on Sunday would bankrupt smaller enterprises and lead to even higher unemployment.

Chancellor Gerhard Schroeder, who is vacationing in Italy, has steered clear of the controversy. But he may not be able to remain above the fray for very long. The Sunday shopping ban is shaping up as a key issue in five state elections to be held this autumn--and the outcome will determine whether Schroeder's government can push further legislation through the upper house of parliament.

CAPTION: Berliners flock to the Kaufhof department store this month in defiance of the Sabbath ban.