Answer: This is a very timely question. I remember hearing on T.V. when I was growing up (at least 30 years ago and more), “Merry Christmas to our Orthodox friends”. So, what was unusual about that? It was on January 6!
In fact, if you come to All Saints Greek Orthodox Church here in Weirton on December 25, and then go to Holy Resurrection Serbian Orthodox Church over in Steubenville on January 6, you will see the exact same Orthodox liturgical service for the Nativity of Christ. We’re Eastern Orthodox. They’re Eastern Orthodox. So we celebrate two Christmases? No. In fact, we celebrate exactly the same Christmas. The root of this dilemma is actually a calendar issue.
As you may remember when we previously discussed why Orthodox Easter and Western Easter were different, the issue was again a calendar issue. For all Eastern Orthodox Christians, Pascha or Easter is celebrated according to the calculation of the Vernal Equinox based on the older Julian calendar. The Gregorian calendar which is used by most of us on a day-to-day basis is the “new” calendar. The difference between the two is approximately 13 days.
So, December 25th on the older Julian calendar is 13 days later than December 25th on the Gregorian calendar, or January 6. So in fact, both the Greek Orthodox faithful and the Serbian Orthodox faithful celebrate Christmas on December 25...
However, unlike the celebration of Easter, each Eastern Orthodox jurisdiction celebrates fixed feasts according to the calendar its hierarchy have elected to follow: the Julian calendar in the case of the Serbian Orthodox Church and certain other national churches, and the Gregorian calendar for the Greek Orthodox Church and some others.
And now for the rest of the story...
Did you know that in the early centuries, the Nativity of Christ was actually
celebrated with the Festival of Lights or Epiphany - the manifestation of God
enlightening the world, on January 6?
After Constantine the Great became Emperor of Rome, the now-free Christian Church decided that the birth of Christ should be given prominence as well as His death and resurrection. For reasons of church propriety, the celebration of the Nativity of Christ was moved to December 25 in Rome in 336 A.D., then in Constantinople by 379 A.D., and then universally celebrated on December 25 by the 6th Century. Epiphany was kept as the celebration of the full manifestation of the Son of God to the world through His baptism. In fact, the “Twelve Days of Christmas” are the days from Christmas to the eve of Epiphany, which makes this time the longest fast-free season for the Greek Orthodox calendar.
Isn’t it interesting that by holding to the old calendar calculations, some of our Orthodox brethren celebrate Christmas on the date from the new calendar that Christmas was originally celebrated before the early part of the 4th Century? That will occur at least until the next date adjustment between the Julian and Gregorian calendars which will add another day of separation between the two. But that won’t happen for a while. And besides, that’s another story...