Christmas is a Christian feast of the incarnation and birth of Jesus Christ. Christmas season lasts from the evening worships of the feast of Nativity until the Sunday after the feast of the Epiphany (or Three Kings). This feast coincides with the traditional date of the winter solstice, which was the feast of the rebirth of the sun. Initially, only the first Christmas Day was celebrated (according to the Gregorian calendar it was December 25). Since the reformation,  people began to celebrate Christmas one day in advance, on Christmas Eve (December 24). In the Orthodox Church, Christmas is celebrated according to...