The word primacy is derived from the Latin word primus, first. The primacy of St. Peter means the office which St. Peter held (and which his successor holds today), that is, the first place in the Church of Christ. And it is not merely the first place in honour or dignity, but the first place in jurisdiction, in authority. When we say Christ conferred the primacy on St. Peter (and his successors), we mean that He made St. Peter His vicar, His direct representative clothed with His own authority, infallibly guided to lead men on the right path by exercising the office of universal teacher of faith and morals.
ST. PETER'S OFFICE
To prove that St. Peter (and his successors each in turn) received such a primacy as we have defined above, it will be necessary to establish the following facts:
a. That Christ singled out St. Peter for a peculiar office, distinct from that of the other Apostles, of teaching and governing the whole Church by his supreme authority;
b. That Christ actually conferred upon St. Peter the duties and powers of that office;
c. That St. Peter actually exercised that office.
Christ singled out St. Peter for the primacy.
Christ is, and ever must remain the head of His Church. Yet Christ made the Church a visible society, the service and value of which must be realised here in this visible world. The Church then had to have a visible head. Christ, however, was to ascend into Heaven and to be no longer visible as Man upon earth. It is the very nature and logic of this situation that requires a visible head of the Church on earth. Now, Christ singled out St. Peter as this head for:
Christ made Peter the Rock upon which the Church is built. After Peter had professed the divinity of Christ, Our Lord said to him (Matt. 16, 18): “I say to thee: That thou art the singular pronoun. This declaration had reference to Peter alone, and not to the other Apostles. Again: Christ made a special prayer for Peter, that he might not fail, telling him that the devil had wished to conquer him particularly (in view of his supreme office), and ordering Peter to confirm the others (Luke 22; 31,32): Simon, Simon, behold Satan bath desired to have you that he may sift you as wheat: but I have prayed for thee that thy faith fail not: and thou being once converted, confirm thy brethren.” Notice again that the singular pronoun makes the declaration refer to Peter alone. Peter was to confirm, i.e., to strengthen the Church as a true and solidly built foundation.
Christ conferred on Peter alone the “keys,” i.e., the supreme mastership of the Kingdom of Heaven, the Church. He said to Peter (Matt. 16; 19.): I will give to thee the keys of the Kingdom of Heaven. And whatsoever thou shall bind on earth, it shall be bound also in heaven.”
Christ actually conferred the Primacy upon St. Peter The promises of Christ, who is the all-perfect God as well as Man, are sufficient to account for the conferring of the promised office; for God necessarily fulfils His promises. Still, we have a special and separate ceremony in which the office was actually conferred. After the Resurrection, on the occasion of His third appearance before His disciples, Christ singled out Peter and said to him (Jn. 21; 15-17): “Simon, son of John, lovest thou me more than these? He saith to him: Yes Lord, thou knowest that I love thee. He saith to him: Feed my lambs. He saith to him again: Simon, son of John, lovest thou me? He saith to him: Yes Lord, thou knowest that I love thee. He saith to him feed my lambs. He saith to him the third time: Simon, son of John lovest thou me? Peter was grieved, because he had said to him the third time, Lovest thou me? And he said to him: Lord, thou knowest all things, thou knowest that I love thee. He said to him fed my sheep.” Thus the whole flock of Christ, sheep and lambs, was placed under the supreme sheperdship of St. Peter. The solemnity of the occasion, the repetition of the question, the impressive insistence of Our Lord upon an answer, His no less impressive commission when the answer was given all these circumstances mark this act of Our Lord as no ordinary act, but as one of deep significance. Christ had often spoken of His church as a sheepfold, and in the solemn words of this text he made Peter (and, as we shall see, his successors, each in turn) the supreme shepherd the supreme authority, in the Church.
Peter actually exercised the Primacy.
Peter, though not the oldest Apostle, nor the first called by Christ, took charge of the Church immediately after the ascension of Christ. He presided at the election of Matthias to the place left vacant by the defection of Judas. He was the spokesman for all the Apostles when the people, amazed at the “power of tongues,” knew not what to think or say of them. He definitely settled the question of admitting the Gentiles to the Church. He presided at the meeting or “council” of the Apostles at Jerusalem. the exercise of the primacy by Peter was always recognised as right and proper. The Evangelists always mention Peter first in any list, complete or partial, of the Apostles, and St. Matthew says, “The names of the twelve apostles are these: The first: Simon who is called Peter . . .” the tradition of the Church has ever recognised the exercise of the primacy as a historical fact in Peter's case, and as the right and duty or his successor. Indeed, in the Council of Ephesus it was plainly stated that every age had recognised St. Peter, prince of the Apostles, as the foundation and chief authority in the Church, and the Pope then reigning (Celestine) stood to St. Peter as “his successor in order and in holder of place.” Since Peter's office did not die with Peter, and since the Church and her mission is for “all nations..... all days,” the office of St. Peter must obviously descend to his legitimate successor.
Even as the Apostles were not deprived of the fullness of “this ministry and apostleship” by the treason and death of Judas, but elected a successor to be with them the witness of Christ's resurrection, It so the Church is not to be left without the necessary ministry and apostleship of its visible head. Christ promised to remain with the Church “ even to the consummation of the world.” That the Church must exist all days,” is, therefore, a certainty; and, if it is to exist as Christ formed it, it must have its visible head. And this head must be the successor of Peter, clothed with St. Peter's power and authority.
The successor of St. Peter is the Pope, the Bishop of Rome, Supreme Pontiff of the Church. The supreme head of the Church, he whose office is that of feeding the flock of Christ, must, in the essential matters of faith and morals, be actually unable to poison that flock with erroneous teaching.
In a word, Peter (and his successors) must be infallible when, in an essential matter of faith or morals, as teacher and ruler of the whole Church, even if he is right or wrong, good or bad, in human conduct . This claim to infallibility is sometimes regarded by those outside the Church as monstrous; and so it would be if it were a mere human claim.
But it is not only reasonable, but actually a requirement when we consider what the Supreme Pontiff has to do. Can he teaching the whole Church in an essential matter of faith or morals in the name of Christ and by His authority teach falsehood? Christ, then, is falsified! Can he feed it the poison of error? As a man the Pope may be weak, sinful, fallible; but when he speaks officially to the whole Church in a matter of faith or morals, then he is exercising the office Christ gave him to exercise; then he is speaking in the very power and authority of Christ; then he is the spokesman of Christ himself and shall Christ's spokesman be able to teach falsehood to Christ's faithful? If so, then Christ himself is deceived and His word falsified, for, if error could be definitely taught and universally accepted as truth in His Church, the gates of hell could and would prevail against the Church.