The head of the Russian Orthodox Church on Saturday urged the government to listen to protesters demanding free elections.
Patriarch Kirill warned both sides that Russia cannot afford another revolution.
"The government should, through dialogue and by listening to society, correct the course and then everything will be fine," he said in an interview broadcast Saturday, the day on which Russians and other Orthodox Christians celebrate Christmas.
Tens of thousands of people turned out for two demonstrations in Moscow to protest vote fraud in last month's parliamentary election and call for an end to Prime Minister Vladimir Putin's 12-year rule.
A third demonstration is planned for Feb. 4, a month ahead of a presidential election that Putin hopes will extend his power for at least six more years. He first served as president from 2000 to 2008.
The patriarch, whose church has close ties to the Kremlin, spoke of the need to preserve a strong state.
He warned the protesters against being used by those fighting for political power, comparing the opposition leaders to the Bolsheviks whose 1917 revolution brought down czarist Russia.
"We destroyed the country, and why did this happen? Because in general the just protests of the people were cleverly used by political forces fighting for power," Kirill said.
The same thing happened again with the protests that led to the collapse of the Soviet Union in 1991, the patriarch said.
The challenge for Russia today, he said, is for the protests to lead to political change but not to shake the foundations of the state.
The protesters have demanded a rerun of the parliamentary election and the dismissal of the Central Election Commission chief.
Putin has promised to allow more political competition and to take steps to ensure the transparency of the March 4 presidential election, but so far he has shown no willingness to consider the protesters' demands or to ease his centralized control over the political system.