Dr. Rodney Moss (Johannesburg):
Depositum fidei sancte custodire et fideliter exponere … the service of primacy for the faith
The Dogmatic Constitution Pastor Aeternus (1870 ) of the First Vatican Council situated the primacy of the Bishop of Rome within the ancient tradition of the Church. We see in this ancient tradition that according to St. Ignatius of Antioch the Church of Rome holds the "presidency of love" (Letter to the Romans, 52 ) while St. Irenaeus states:
And for this Church, because of her superior origin, all churches must
agree, that is, all the faithful in the whole world, and it is in her that the
faithful everywhere have maintained the apostolic tradition.
( Adv. Haer. 3,3,3 )
The local Church of Rome owed her prestige and primacy to her link with the memory of the apostles Peter and Paul. Her ancient tradition linked to these two apostles made her the guarantee of authentically belonging to Christ. The Church of Rome was a memorial and a point of reference for the apostolic faith and hence was seen as a "watchman", a "sentinel" and a "touchstone". The leadership exercised by the Bishop of Rome within the College of Bishops lay in this function of "watch" (primacy) over all the churches. Hence the constitution sees the ministry of the Roman Pontiff as one of service towards the unity of the whole people of God.
And in order that the episcopate also might be one and undivided, ,and
that by means of a closely united priesthood the multitude of the faithful
might be kept secure in the oneness of faith and communion, he set Peter
over the rest of the apostles.
The constitution further states that the power of the Supreme Pontiff is not prejudicial to the ordinary and immediate power of Episcopal jurisdiction; rather it is "…asserted, strengthened and protected by the supreme and universal pastor". The primacy of the Pope, according to the Second Vatican Council, is exercised in the guardianship and care for the unity of all the churches. Lumen Gentium states: "The Roman Pontiff, as the successor of Peter, is the perpetual and visible source and foundation of the unity both of the bishops and the whole company of the faithful" (no. 23). At its best the authority of the watchman, the primate, is exercised in the duty in love to question the churches in what concerns the demands of truth and in their fidelity to apostolic teaching.
In conclusion it is worth noting that Orthodox, Anglican and Lutheran theologians meeting in various international commissions in dialogue with the Catholic Church see some exercise of the primacy of the Bishop of Rome as "normal", "desirable" or "useful" to varying degrees. In memorable words by Athenagoras, Patriarch of Constantinople and in spite of the rupture in Christian unity the See of Rome is still held to be "first in honour of rank in the living body of Christian churches dispersed throughout the world" (Athenagoras, Address to Paul V1, 26th October 1967).