The Petrine ministry, which according to Paul VI should unite, presents itself rather as the principal obstacle to the union of Christians. It is therefore necessary to study it in order to liberate it from that which is not essential. Themes: authority of the Church; primate and patriarch; the historical development of the concept of the primate; ecumenical reality of the Petrine ministry; Vatican I and Vatican II.
Avenues of research: biblico-patristic (Ignatius, Irenaeus, Maximus, Theodore the Studite; Synodal practice of the first millennium); historico-ecclesiastical, spiritual, iconographic.
To follow the development of the idea of the primate through history, whether of church politics or dogma.
O. Cullmann et al., Il primato di Pietro nel pensiero contemporaneo, Bologna 1965;
F. Dvornik, Byzance et la primauté romaine, Paris 1964;
K. Schatz, Der päpstliche Primat, Würzburg 1990;
W. Kasper (ed.), Il ministero petrino: cattolici e ortodossi in dialogo, Roma 2004.