The Bible points out only seven “true” holidays (or holy days) – the festivals of Leviticus 23 (the Sabbath, the Firstfruits, the Passover/the Feast of the Unleavened Bread, the Feast of Weeks, the Feast of Trumpets, the Day of Atonement, the Feast of Tabernacles). Those were all signs pointing to Christ who would take away all the sin of the world for those that believe in His sacrifice. Those holidays had pure Biblical meaning.
While the weekly Sabbath holiday changed from a Saturday to a Sunday celebration because of Jesus’ resurrection, the Old Testament celebrations all vanished from the Christian calendar.
Since then, Christians added other holidays in order to honor and remember the two greatest events in Christianity – Easter and Christmas. Easter coincides with the Jewish Passover (actually fulfilling it). Christmas came about as a response to Pagan holidays that dominated the calendars. Instead of celebrating a holiday called Saturnalia, the worship of a sun god on December 25th, Christians decided to celebrate the birth of Christ. Its popularity exceeded Saturnalia.
While not commanded in the Bible, Christmas certainly deserves a place in our holiday celebrations. Its meaningfulness is determined by how much emphasis we give to the birth of Christ. For one day a year, Christmas provides a unique opportunity to share the love of Christ. That makes it a true holy day.