Patriarch Alexey II conducted the late-night services at Moscow's Christ the Saviour's Cathedral, which was televised live.
ITAR-TASS, a Russian news agency, reported Alexey's message urged Christians to heed God's gift of love for "all people around us."
"Happiness and the plenitude of everyday life are in love, mutual responsibility and readiness to devote your life to those who love," he said.
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