Christmas and Advent are not God's holidays recorded in the Bible. This day is the biggest festival in Christianity and of the world. Even a month before Christmas, all kinds of decorations are hung in the streets and shops, and even those who do not believe in God exchange gifts and enjoy the Christmas season. Christmas is a compound word originated from the term “Christ’s Mass,” and means the commemoration of the birth of Jesus Christ. All told, transcending its religious meaning, Christmas has been established as a public holiday in many countries and become a much-awaited day for many people in the world. Do you know when people started to celebrate Christmas?