Originally, the 25 December. The day the emperor took the aurelian of Roman. The birthday celebration of the solar deity since 1990.274 most respected Roman gods as if they were celebrating today. Is a day of celebration of the emperor to the body. Because the emperor, like the sun. Give light to the human life. But the Christians in the Roman Empire.Turned to celebrate the birth of Jesus, which is like the light of the world. And as the moon is bright in the night.