LAS CRUCES — Recently I saw or heard words about Orthodox Christmas on Jan. 7. Several people phoned or e-mailed to wish me Merry Christmas and I would tell them that we Orthodox in Las Cruces are on the so-called "new calendar."

So what is this calendar biz all about? This is not easy to answer.

The Julian calendar is the "old calendar." In 46 BCE, emperor Julius Caesar commissioned astronomers to calculate it. The Julian year has 365 days and 12 months with a leap day every fourth year, just like the one we now use. But every century they had to add three additional days to adjust for miscalculation; that was the best they could do.

Centuries later, Pope Gregory XIII initiated a reform to correct this error. The calendar named after him came into use in 1582. Adoption was ragged and uneven at first, but most countries fell in line. The astronomical issues are complex so let's simply accept that these calendars differ 13 days.

The Gregorian (new) calendar is not perfect. No calendar is, because of the difference between lunar and solar cycles. The new calendar will add another day in 2100 to correct for error.

So let's start here: All Orthodox Christians celebrate Christmas on Dec. 25. When the calendar we Americans use, the one hanging on your kitchen wall, says Jan. 7, the old Julian calendar reads Dec. 25. The Christmas date is the same; the calendars make it different "on the ground."

Christian Orthodoxy is divided into a number of ethnic jurisdictions in the U.S. The differences are in local custom and original language, not in theology or worship. Some observe old calendar: Serbians, Ukrainians, Georgians, the Jerusalem patriarchate, and the Russian Orthodox Church outside Russia (ROCOR). The majority of Orthodox in the U.S. use new calendar. So you can wish your old calendar friends Merry Christmas on the 7th of January, but the rest of us are on the same page as you are.

The big discrepancy in calendar calculation comes with Easter. The Easter date is calculated differently between Orthodoxy and other Churches.

In 2013, we are as far apart as we can get: five weeks. Western Easter is March 31 and Orthodox is May 5. We share the same date for Easter only about six times in every 20 years and that's not intentional, but more accidental. Orthodox Easter is reckoned on the Julian (old) calendar in all Orthodox churches to this day, and that is chiefly why the festival dates differ. The difference between Easter dating is the difference most people usually notice, more so than Christmas, because so many Orthodox churches follow the new calendar for Christmas.

So why are Orthodox churches old calendar? The main reason is that the Orthodox did not want to follow a calendar that imposed a pretense of unity among Christians where none existed. That may sound strange to Americans who like to smooth everything over ("all Christian churches are the same, just different in ") but it is indeed the main reason. The point is not the calendar, but the faith. We are in many ways different from other churches. If we are not united in the faith, then why pretend to be so at major festivals of the year? Orthodox Christians are not exactly known for jumping on the ecumenical bandwagon. Hence the compromise: Christmas on the new calendar, Easter on the old. To no one's surprise, this satisfied some and angered others. But that's our problem.

Our national church remains on the old calendar. Only the missions are on the new calendar. C'est la vie.

Fr. Gabriel Rochelle is pastor of St. Anthony of the Desert Orthodox Mission. For more information, visit