Most Orthodox Christians celebrate Christmas according to the Julian calendar on January 7. Western Christian churches mark the holiday according to the Gregorian calendar. Above, servicemen in Belarus' Interior Ministry's special unit queue up to kiss an Orthodox cross after a service at a military base in Belarus' capital, Minsk.
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A Palestinian Orthodox Christian girl lights a candle in a church during Christmas celebrations in Gaza City.
Russian Orthodox Patriarch Kirill leads a Christmas service attended by Prime Minister Dmitry Medvedev (second from left) in the Cathedral of Christ the Saviour in Moscow.
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The head of Russia's dominant church urged its citizens to adopt
children, after President Vladimir Putin signed a controversial law
barring Americans from adopting Russian children.
Masked men symbolising death are seen as they perform Christmas carols, known locally as "Kolyadki", in the central western Ukrainian city of Lviv.
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Orthodox women attend Christmas midnight mass led by the newly elected Pope Tawadros II, head of the Egyptian Coptic Orthodox Church, at the al-Abasseya Cathedral in Cairo.
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People attend a ceremonial burning of dried oak branches, the Yule log symbol for the Orthodox Christmas Eve, in front of a church 80 kilometres west of Belgrade, Serbia.
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Russian President Vladimir Putin attends a Christmas service in a church in Sochi.
The Greek Orthodox Patriarch of Jerusalem, Theophilos III, arrives at the Church of the Nativity in the biblical West Bank town of Bethlehem, the traditional birthplace of Jesus Christ.