When a dispute arises in the Church regarding the sense of Scripture the subject is referred to the Pope for final adjudication. The Sovereign Pontiff, before deciding the case, gathers around him his venerable colleagues, the Cardinals of the Church; or he calls a council of his associate judges of faith, the Bishops of Christendom; or he has recourse to other lights which the Holy Ghost may suggest to him. Then, after mature and prayerful deliberation, he pronounces judgment and his sentence is final, irrevocable and infallible.

If the Catholic Church were not fortified by this Divinely-established supreme tribunal, she would be broken up, like the sects around her, into a thousand fragments and religious anarchy would soon follow. But by means of this infallible court her marvellous unity is preserved throughout the world. This doctrine is the keystone in the arch of Catholic faith, and, far from arousing opposition, it ought to command the unqualified admiration of every reflecting mind.

These explanations being premised, let us now briefly consider the grounds of the doctrine itself.

The following passages of the Gospel, spoken at different times, were addressed exclusively to Peter: “Thou art Peter; and on this rock I will build My Church, and the gates of hell shall not prevail against it.”[176] “I, the Supreme Architect of the universe,” says our Savior, “will establish a Church which is to last till the end of time. I will lay the foundation of this Church so deep and strong on the rock of truth that the winds and storms of error shall not prevail against it. Thou, O Peter, shalt be the foundation of this [pg 126] Church. It shall never fall, because thou shalt never be shaken; and thou shalt never be shaken, because thou shalt rest on Me, the rock of truth.” The Church, of which Peter is the foundation, is declared to be impregnable—that is, proof against error. How can you suppose an immovable edifice built on a tottering foundation? For it is not the building that sustains the foundation, but it is the foundation that supports the building.

“And I will give to thee the keys of the Kingdom of Heaven.”[177] Thou shalt hold the keys of truth with which to open to the faithful the treasures of heavenly science. “Whatsoever thou shalt bind on earth shall be bound also in Heaven.”[178] The judgment which thou shalt pronounce on earth I will ratify in heaven. Surely the God of Truth is incapable of sanctioning an untruthful judgment.

“Behold, Satan hath desired to have you (My Apostles), that he may sift you as wheat. But I have prayed for thee (Peter) that thy faith fail not; and thou, being once converted, confirm thy brethren.”[179] It is worthy of note that Jesus prays only for Peter. And why for Peter in particular? Because on his shoulders was to rest the burden of the Church. Our Lord prays for two things: First—That the faith of Peter and of his successors might not fail. Second—That Peter would confirm his brethren in the faith, “in order,” as St. Leo says, “that the strength given by Christ to Peter should descend on the Apostles.”

We know that the prayer of Jesus is always heard. Therefore the faith of Peter will always be firm. He was destined to be the oracle which all were to consult. Hence we always find him the [pg 127] prominent figure among the Apostles, the first to speak, the first to act on every occasion. He was to be the guiding star that was to lead the rest of the faithful in the path of truth. He was to be in the hierarchy of the Church what the sun is in the planetary system—the centre around which all would revolve. And is it not a beautiful spectacle, in harmony with our ideas of God's providence, to behold in His Church a counterpart of the starry system above us? There every planet moves in obedience to a uniform law, all are regulated by one great luminary. So, in the spiritual order, we see every member of the Church governed by one law, controlled by one voice, and that voice subject to God.

“Feed My lambs; feed My sheep.”[180] Peter is appointed by our Lord the universal shepherd of His flock—of the sheep and of the lambs—that is, shepherd of the Bishops and Priests as well as of the people. The Bishops are shepherds, in reference to their flocks; they are sheep, in reference to the Pope, who is the shepherd of shepherds. The Pope, as shepherd, must feed the flock not with the poison of error, but with the healthy food of sound doctrine; for he is not a shepherd, but a hireling, who administers pernicious food to his flock.

Among the General Councils of the Church already held I shall mention only three, as the acts of these Councils are amply sufficient to vindicate the unerring character of the See of Rome and the Roman Pontiffs. I wish also to call your attention to three facts: First—That none of these Councils were held in Rome; Second—That one of them assembled in the East, viz: in Constantinople; and, Third—That in every one of [pg 128] them the Oriental and the Western Bishops met for the purpose of reunion.

The Eighth General Council, held in Constantinople in 869, contains the following solemn profession of faith: “Salvation primarily depends upon guarding the rule of right faith. And since we cannot pass over the words of our Lord Jesus Christ, who says, ‘Thou art Peter, and on this rock I will build My Church,’ what was said is confirmed by facts, because in the Apostolic See the Catholic religion has always been preserved immaculate, and holy doctrine has been proclaimed. Not wishing, then, to be separated from this faith and doctrine, we hope to merit to be in the one communion which the Apostolic See preaches, in which See is the full and true solidity of the Christian religion.”