As the Church marks the 1700th anniversary of the Council of Nicaea (325–2025), Fr. Thomas Joseph White, O.P., Rector of the Angelicum, speaks with Prof. Lewis Ayres, one of the world’s leading experts on early Christian theology, about the enduring significance of Nicaea.
They discuss what the Council achieved, how its vision of Christ and the Trinity continues to shape Christian faith today, its role in Catholic-Orthodox dialogue, and the significance of Pope Leo XIV’s upcoming visit to Turkey to commemorate this milestone in Church history.
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0:00 Introduction
1:20 Background to the Council of Nicaea
6:00 What Is Arianism?
10:03 What’s Wrong with Arianism?
11:42 What Does Nicaea Say? The Two Statements of the Creed
13:55 The Meaning of “Homoousios” in the Creed
15:46 Reception of Nicaea & Theology of the Trinity
19:41 Why Do Expressions of the Faith Change Over Time?
21:45 Development of Doctrine
24:07 Why Does Nicene Theology Matter Today?
27:17 The Nicene Creed & Scripture
30:03 The Nicene Creed & Ecumenism (Catholic, Orthodox, Protestant)
33:22 Visit of Pope Leo XIV to Turkey & Catholic-Orthodox Relations
35:00 Advice for Young Theologians & Theological Literacy
38:00 Conclusion