This volume is the outcome of the first international conference held in Istanbul in December 2022 and promoted by the Fondazione per le scienze religiose. It delves deeply into the Council of Nicaea’s historical significance, particularly its role in shaping the Nicene Creed. The various contributions meticulously examine the Creed’s development and its crucial role in defining Christian doctrine. Fresh perspectives are applied to understudied aspects of the Creed, such as its reception in different regions or its influence on theological debates. By charting new paths for future research, this work promises to be a valuable resource for scholars and anyone interested in the enduring legacy of the Council of Nicaea and its Creed.