For the first time in history, the leader of the Orthodox Church will be attending the installation of a pope of the Roman Catholic Church.
The Ecumenical Patriarch Bartholomew of Constantinople will be present for the installation mass for Pope Francis on Tuesday. This is the first time an Ecumenical Patriarch has been present for this Catholic mass since the Great Schism of 1054, when the Eastern and Western Church cut ties with one another.
In an interview with a television network in Istanbul, Turkey, Bartholomew explained that the decision to attend was a gesture to showcase improving relations between the two Ancient Churches.
"It is a gesture to underline relations which have been developing over the recent years and to express my wish that our friendly ties flourish even more during this new era," said Bartholomew.
Other faith leaders, including other Orthodox Church officials, are expected as well. Metropolitan Tikhon, the head of the Orthodox Church in America, will be present. The Russian Orthodox Church's Patriarch will be sending his envoy.
Archpriest Leonid Kishkovsky, chairman of the Department of External Affairs and Interchurch Relations for The Orthodox Church in America, told The Christian Post that the attendance was "a significant gesture."
"His attendance at the inaugural mass is a significant gesture, one which will enhance and strengthen Orthodox-Catholic relations," said Kishkovsky. "The Ecumenical Patriarch is the first in honor among the Orthodox Churches, and is the one who initiates common action by the Orthodox Churches."
While Kishkovsky told CP that the two church bodies becoming one was "not in prospect at this time," he did note that the opportunities for cooperation were high.
"New possibilities may be emerging, not only for dialogue but also for collaboration," said Kishkovsky.
"On many issues of traditional Christian faith and moral teach the Orthodox and Catholic visions are in harmony."
In 1054, the Eastern and Western Churches of Christianity split up in an event known as the Great Schism. The fracturing of the churches came in large part over disagreement on the extent of power the Bishop of Rome should have.
According to Suzan Fraser of The Associated Press, this is not the first time that Ecumenical Patriarch Bartholomew has gone to Vatican City.
"Bartholomew has made several previous visits to the Vatican, including attending the funeral of Pope John Paul II in 2005," wrote Fraser.
"Bartholomew also hosted [Pope Benedict XVI] during a 2006 visit to Istanbul, the sprawling city formerly called Constantinople and the ancient spiritual center of the Orthodox churches."