MOSCOW — From morning all through the night, tens of thousands of Russians have been lining up since Saturday in the cold with just one aim: to kiss a glass-covered reliquary that they believe holds the Virgin Mary’s belt.

They shuffle along, waiting for up to 12 hours without complaint in a line that stretches for miles. Within a few days, the organizers say, the wait could reach 24 hours. At any given time there are about 25,000 people, according to news media estimates, and as of Wednesday morning, 285,000 true believers had earned their moment before the belt, said the St. Andrew the First-Called Foundation, which organized the tour.

As befits his status as the arbiter of most things Russian, Prime Minister Vladimir V. Putin was the first to greet the holy relic when it arrived on Oct. 20 in St. Petersburg from a Greek Orthodox monastery on Mount Athos in Greece for a monthlong tour of Russia.

Of all the industrial nations, perhaps only Russia outdistances the United States in the religiosity of its people, two million of whom venerated the belt before its final stop in Moscow.