Abstract
The author works in his study on the finding that the celebration of the ecumenical councils permeates through the whole Church history as a red thread, and the councils represent the most important expressions of ecclesial communion (communio) from the beginning of the Christianity to the present time. The Second Vatican Council aroused a special interest, even among scholars and hierarchy, who began to deal more intensively with the issue of synodality in the Church.
The author therefore in his study examines the ancient councils and their authority as a living source of inspiration for the modern time and for the perception of Vatican II. He deals with general questions of the meaning of the council, with their course, with principles of synchronic and diachronic consensus, with Church reception of councils, with relation of the councils and papacy in ancient times, with the revision of the conciliar outcomes, with the presence of non-bishops, etc.