At Nicaea's Ruins, Pope and Orthodox Patriarch Call for Christian Unity on 1,700th Anniversary

Pope Leo XIV urged Christians to pursue unity on Friday during an ecumenical prayer service on the shores of Lake Iznik, marking 1,700 years since the Council of Nicaea.

On the second day of his visit to Turkey, the pope flew to Iznik — the ancient city of Nicaea — where he joined Ecumenical Patriarch Bartholomew I and other dignitaries at the site linked to the historic council.

Clad in ceremonial robes, the leaders assembled on a wooden platform overlooking the ruins of a 4th-century basilica that marks the spot where hundreds of bishops met in 325 to formulate the Nicene Creed, a statement of faith that remains central to Christianity. Under warm sunshine they prayed together in several languages while a choir performed a cappella hymns in English, French, Greek, Latin and Turkish.

Speaking in English, the pope recalled how the council unified the early Church by rejecting the Arian doctrine that denied Christ's full divinity, calling the anniversary "a precious opportunity to ask ourselves who Jesus Christ... is for each one of us personally."

"We are all invited to overcome the scandal of divisions that unfortunately still exist and to nurture the desire for unity," he said, and the leaders then recited the Nicene Creed together in English.

Despite doctrinal differences that culminated in the Great Schism of 1054 — which separated the Western Roman Catholic and Eastern Orthodox churches — the two communions continue formal dialogue and occasionally share commemorations. Patriarch Bartholomew echoed the call for unity: "With the fervour of the faith of Nicaea burning in our hearts, let us run the course of Christian unity that is set before us."

The pope's visit comes amid strains within Orthodoxy, intensified by Russia's actions in Ukraine, which have widened the rift between the Moscow and Constantinople patriarchates. He also firmly rejected the use of religion to justify violence: "We must strongly reject the use of religion for justifying war, violence, or any form of fundamentalism or fanaticism. Instead, the paths to follow are those of fraternal encounter, dialogue and cooperation."

Turkish media reported that police detained Mehmet Ali Agca in Iznik. Agca, who shot and seriously wounded Pope John Paul II in 1981 and was released from prison in 2010, told reporters he had hoped to meet the pope and said, "I hope we can sit down and talk in Iznik, or in Istanbul, for two or three minutes."

Earlier in his four-day visit, the pope urged President Recep Tayyip Erdogan in Ankara to embrace Turkey's role as a source of "stability and rapprochement between peoples." He also attended a prayer service at Istanbul's Cathedral of the Holy Spirit; security measures briefly closed a major thoroughfare to allow his convoy to pass.

Visibly more at ease than on his first day, the pope encouraged local Catholics to reach out to migrants and refugees in Turkey — nearly three million people, most of them Syrians — and criticised harsh government policies toward migrants elsewhere, calling their treatment "extremely disrespectful."

Although the visit attracted relatively little public attention in this predominantly Muslim country of about 86 million, residents noted the disruption caused by security measures. "It's an important visit for Istanbul, but we are the ones suffering," said a 55-year-old woman named Fatmah. "Of course it's normal to take security measures, but no one thinks about the workers."

Pope Leo XIV is the fifth pontiff to visit Turkey in modern times, following Paul VI (1967), John Paul II (1979), Benedict XVI (2006) and Francis (2014).