Informally, Russia has long marked St. Patrick's Day, joining the rest of the world in the March 17 celebration of Irish culture that includes lots of green and lots of drinking. This year, however, the Russian Orthodox Church is doing something different.

It's formally celebrating St. Patrick's Day for the first time — but on March 30.

Earlier this month, the church announced it would finally recognize the day in commemoration of Saint Patrick, a missionary who had lived in the 5th century and is now widely known as the patron saint of Ireland. Orthodox leaders told the Russian media they hoped that recognizing Saint Patrick and a number of other western saints would show the shared roots of different branches of Christianity, before the Schism of 1054 that divided the faith into East and West.

Despite this, the divide between the two wings of Christianity means that the Russian Orthodox Church will not celebrate St. Patrick's Day along with the rest of the world. While the Catholic Church adopted the Gregorian calendar in the 16th century, the Russian Orthodox Church still uses the older Julian calendar. The two calendars are about two weeks out of sync.

This means that the day of St. Patrick's death — March 17 in the Gregorian calendar — falls on March 30 for the Russian Orthodox Church.

The March 30 date seems likely to extend Russia's St. Patrick's Day festivities rather than replace them. Russia has held events celebrating the day since the fall of communism. More than 15,000 people are expected to attend this year's official parade in Moscow, which will take place on March 18; the parade itself is part of a larger spread of events related to Ireland that take place March 15 to 26.

In a statement given to the Govorit Moskva radio station, the Irish government said it was glad the Russian Orthodox Church had made the decision. “We hope to see our friends in Moscow on all of our Irish events in the next two weeks,” said Arthur Hendrick, consul at the Irish Embassy in Moscow.

For members of the Orthodox faith, celebrating two St. Patrick's days may not be an option: March 17 falls in the middle of the Orthodox observance of Lent, when many religious Russians abstain from alcohol. Father Igor Fomin, head of a church at the Moscow State Institute of International Relations, told Tass news agency that getting drunk in honor of a saint is like being heavily intoxicated at your mother’s gravesite.

“I am very happy that our St. Patrick’s Day falls on a different date, that way the traditions associated with it, that are strictly cultural and not religious can be ignored,” Fomin said.

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