In the Turkish city of Iznik, the ancient site of Nicaea, the 1700th anniversary of the First Ecumenical Council was marked with a historic ecumenical service. The event was especially significant as Pope Leo XIV and Patriarch Bartholomew of Constantinople jointly recited the Nicene-Constantinopolitan Creed without the Latin addition of filioque for the first time. This momentous act took place at the archaeological site of the ancient Basilica of St. Neophytus, where the ecumenical prayer service became the central highlight of the anniversary celebrations, according to Vatican News.

Pope Leo XIV addressed the gathering, calling on Christians to overcome the shame of division and to witness to the world together in Christ. He emphasized that the confession of the common faith, as formulated by the Fathers of the Council of Nicaea, remains a guiding principle on the path to Christian unity.

Patriarch Bartholomew also highlighted the significance of the gathering, noting that the meeting in Nicaea was not only a remembrance of the past but also a living testament to shared faith. "We are returning to the source of Christianity to move forward," he said, underscoring the importance of the Nicene Creed for the entire Christian tradition.

The celebrations were attended by Patriarch Theodoros of Alexandria, representatives from the Antiochian and Jerusalem Churches, and leaders of Christian communities in Turkey. This marked the first-ever visit of a pope to the historic city of Nicaea.

Following the prayer service, Pope Leo XIV and Patriarch Bartholomew signed a joint declaration expressing hope that the anniversary of the Council would serve as an opportunity for "new and bold steps toward Christian unity" and contribute to fostering peace among nations.

The year 2025 marks the 1700th anniversary of the First Ecumenical Council, which convened in the city of Nicaea in 325. The Council was a pivotal event in Christian history, as it led to the formulation of the Nicene Creed, a statement of faith that continues to unite Orthodox, Catholic, and many Protestant communities. At the time, the Church rejected the teachings of Arius and affirmed the full divinity of Jesus Christ.

This historic celebration in Iznik underscores the enduring significance of the Nicene Creed, which remains a cornerstone of Christian belief and a symbol of unity in a divided world.