On the second day of his first foreign trip, Pope Leo XIV visited the historical site of the First Council of Nicaea in Iznik, Turkey. This location is significant as it was where early Christian leaders convened 1,700 years ago to formulate the creed still used in churches today.
During his visit, the first American pope participated in a prayer alongside Ecumenical Patriarch Bartholomew, who is the spiritual head of the world's Eastern Orthodox Christians. The prayer took place amidst the archaeological remnants of a lakeside church, where bishops gathered in 325 AD to address divisions within the nascent Christian Church.
Pope Leo XIV delivered a speech at the site on the shore of Iznik Lake, stating, "We must strongly reject the use of religion for justifying war, violence, or any form of fundamentalism or fanaticism." He emphasized that the appropriate paths involve "fraternal encounter, dialogue and cooperation."
Throughout his trip, Pope Leo XIV has advocated for unity, both among Christian denominations and across different religions and communities. In a prior address with Turkish President Recep Tayyip Erdogan, he highlighted that global division and polarization pose a threat to the future of humanity.
The First Council of Nicaea was convened by Emperor Constantine, who summoned bishops from across the Roman Empire to resolve a doctrinal crisis concerning Jesus's relationship to God. This occurred after approximately 250 years of Christian persecution, which ended when Emperor Constantine permitted freedom of worship. Constantine viewed a unified Church as crucial for stabilizing an empire recovering from civil war.
The most significant theological disagreement stemmed from Arius, an Alexandrian priest who proposed that Jesus, while exalted, was the highest created being but not equivalent to God. The council ultimately rejected Arius's interpretation, affirming that Jesus is "of one substance" with the Father. This theological statement forms the foundation of the Nicene Creed, recited by Catholics today.
The exact location of the council remained unknown until about 11 years ago. Turkish archaeologist Mustafa Sahin identified the site after public workers provided aerial photographs of Lake Iznik. The ruins, which include a basilica's apse and multiple graves, were found submerged under approximately eight feet of water. Due to receding water levels, the full architectural footprint of the basilica is now located on dry land.
Christianity largely remained unified until the Great Schism of 1054, which led to the separation of Catholic and Eastern Orthodox churches due to theological differences and power disputes between Rome and Constantinople (modern-day Istanbul).
On Friday, Pope Leo XIV and Patriarch Bartholomew conducted a joint silent prayer over the exposed ruins at the historic site. Preceding this anniversary, Pope Leo XIV released an apostolic letter recognizing the Nicene Creed as a "common heritage of Christians" and noting its creation when "the wounds inflicted by the persecutions of Christians were still fresh." A joint declaration is scheduled to be signed by the Pope and the Patriarch on Saturday, symbolizing continued efforts toward unity.