No matter what Christian Faith we belong to, we all take it take the Church or faith we follow is the true faith. In a perfect society of Christians without any diverse denominations that would be considered proof in itself.
However, due to historical events and many influences produced either by Satan or man, the Church has been divided into a multitude of denominations, each one claiming to be the True Church of Christ. For Catholics it is the Catholic Church.
On the basis of Mark 3:16, 9:2, Luke 24:34 and 1 Corinthians 15:5, the Catechism of the Catholic Church describes Peter as holding first place among the apostles. It speaks of Peter as the rock on which, because of Peter's faith, Christ said in Matthew 16:18 he would build his Church, which he declared would be victorious over the powers of death. In Luke 22:32, Jesus gave Peter the mission to keep his faith after every lapse and to strengthen his brothers in it. The Catechism of the Catholic Church sees the power of the keys that Jesus promised in Matthew 16:19 to be for Peter alone and as signifying authority to govern the house of God, that is, the Church, an authority that Jesus after his resurrection confirmed for Peter by instructing him in John 21:15–17 to feed Christ's sheep. The power to bind and loose, conferred on all the apostles jointly and to Peter in particular (Matthew 16:19), is seen in the Catechism of the Catholic Church as authority to absolve sins, to pronounce judgments on doctrine and to make decisions on Church discipline.
Proof of the Church's infallibility
That the Church is infallible in her definitions on faith and morals is itself a Catholic dogma, which, although it was formulated ecumenically for the first time in the Vatican Council, had been explicitly taught long before and had been assumed from the very beginning without question down to the time of the Protestant Reformation. The teaching of the Vatican Council is to be found in Session III, cap. 4, where it is declared that "the doctrine of faith, which God has revealed, has not been proposed as a philosophical discovery to be improved upon by human talent, but has been committed as a Divine deposit to the spouse of Christ, to be faithfully guarded and infallibly interpreted by her"; and in Session IV, cap. 4, where it is defined that the Roman pontiff when he teaches ex cathedra "enjoys, by reason of the Divine assistance promised to him in blessed Peter, that infallibility with which the Divine Redeemer wished His Church to be endowed in defining doctrine regarding faith and morals". Even the Vatican Council, it will be seen, only introduces the general dogma of the Church's infallibility as distinct from that of the pope obliquely and indirectly, following in this respect the traditional usage according to which the dogma is assumed as an implicate of ecumenical magisterial authority. Instances of this will be given below and from these it will appear that, though the word infallibility as a technical term hardly occurs at all in the early councils or in the Fathers, the thing signified by it was understood and believed in and acted upon from the beginning. We shall confine our attention in this section to the general question, reserving the doctrine of papal infallibility for special treatment. This arrangement is adopted not because it is the best or most logical, but because it enables us to travel a certain distance in the friendly company of those who cling to the general doctrine of ecclesiastical infallibility while rejecting the papal claims. Taking the evidence both scriptural and traditional as it actually stands, one may fairly maintain that it proves papal infallibility in a simpler, more direct, and more cogent way than it proves the general doctrine independently; and there can be no doubt but that this is so if we accept as the alternative to papal infallibility the vague and unworkable theory of ecumenical infallibility which most High-Church Anglicans would substitute for Catholic teaching. Nor are the Eastern schismatical Churches much better off than the Anglican in this respect, except that each has retained a sort of virtual belief in its own infallibility, and that in practice they have been more faithful in guarding the doctrines infallibly defined by the early ecumenical councils. Yet certain Anglicans and all the Eastern Orthodox agree with Catholics in maintaining that Christ promised infallibility to the true Church, and we welcome their support as against the general Protestant denial of this truth.
Proof from Scripture
In order to prevent misconception and thereby to anticipate a common popular objection which is wholly based on a misconception it should be premised that when we appeal to the Scriptures for proof of the Church's infallible authority we appeal to them merely as reliable historical sources, and abstract altogether from their inspiration. Even considered as purely human documents they furnish us, we maintain, with a trustworthy report of Christ's sayings and promises; and, taking it to be a fact that Christ said what is attributed to Him in the Gospels, we further maintain that Christ's promises to the Apostles and their successors in the teaching office include the promise of such guidance and assistance as clearly implies infallibility. Having thus used the Scriptures as mere historical sources to prove that Christ endowed the Church with infallible teaching authority it is no vicious circle, but a perfectly legitimate logical procedure, to rely on the Church's authority for proof of what writings are inspired.
Merely remarking for the present that the texts in which Christ promised infallible guidance especially to Peter and his successors in the primacy might be appealed to here as possessing an a fortiori value, it will suffice to consider the classical texts usually employed in the general proof of the Church's infallibility; and of these the principal are:
John 14, 15, and 16;
I Timothy 3:14-15; and
Acts 15:28 sq.
In Matthew 28:18-20, we have Christ's solemn commission to the Apostles delivered shortly before His Ascension: "All power is given to me in heaven and in earth. Going therefore, teach ye all nations; baptizing them in the name of the Father, and of the Son, and of the Holy Ghost; teaching them to observe all things whatsoever I have commanded you: and behold I am with you all days, even to the consummation of the world." In Mark 16:15-16, the same commission is given more briefly with the added promise of salvation to believers and the threat of damnation for unbelievers; "Go ye into the whole world, and preach the gospel to every creature. He that believeth and is baptized shall be saved; but he that believeth not shall be condemned."
In Matthew 16:18, we have the promise that "the gates of hell shall not prevail" against the Church that is to be built on the rock; and this also, we maintain, implies the assurance of the Church's infallibility in the exercise of her teaching office. Such a promise, of course, must be understood with limitations according to the nature of the matter to which it is applied. As applied to sanctity, for example, which is essentially a personal and individual affair, it does not mean that every member of the Church or of her hierarchy is necessarily a saint, but merely that the Church, as whole, will be conspicuous among other things for the holiness of life of her members. As applied to doctrine, however — always assuming, as we do, that Christ delivered a body of doctrine the preservation of which in its literal truth was to be one of the chief duties of the Church — it would be a mockery to contend that such a promise is compatible with the supposition that the Church has possibly erred in perhaps the bulk of her dogmatic definitions, and that throughout the whole of her history she has been threatening men with eternal damnation in Christ's name for refusing to believe doctrines that are probably false and were never taught by Christ Himself. Could this be the case, would it not be clear that the gates of hell can prevail and probably have prevailed most signally against the Church?
In Christ's discourse to the Apostles at the Last Supper several passages occur which clearly imply the promise of infallibility: "I will ask the Father, and he shall give you another Paraclete, that he may abide with you forever. The spirit of truth . . . he shall abide with you, and shall be in you" (John 14:16, 17). "But the Paraclete, the Holy Ghost, whom the Father will send in my name, he will teach you all things, and bring all things to your mind, whatsoever I shall have said to you" (ibid. 26). "But when he, the spirit of truth, is come, he will teach you all truth (John 16:13). And the same promise is renewed immediately before the Ascension (Acts 1:8). Now what does the promise of this perennial and efficacious presence and assistance of the Holy Ghost, the Spirit of truth, mean in connection with doctrinal authority, except that the Third Person of the Blessed Trinity is made responsible for what the Apostles and their successors may define to be part of Christ's teaching? But insofar as the Holy Ghost is responsible for Church teaching, that teaching is necessarily infallible: what the Spirit of truth guarantees cannot be false.
1 Timothy 3:15
In 1 Timothy 3:15, St. Paul speaks of "the house of God, which is the church of the living God, the pillar and ground of the truth"; and this description would be something worse than mere exaggeration if it had been intended to apply to a fallible Church; it would be a false and misleading description. That St. Paul, however, meant it to be taken for sober and literal truth is abundantly proved by what he insists upon so strongly elsewhere, namely, the strictly Divine authority of the Gospel which he and the other Apostles preached, and which it was the mission of their successors to go on preaching without change or corruption to the end of time. "When you had received of us", he writes to the Thessalonians, "the word of the hearing of God, you received it not as the word of men, but (as it is indeed) the word of God, who worketh in you that have believed" (1 Thessalonians 2:13). The Gospel, he tells the Corinthians, is intended to bring "into captivity every understanding unto the obedience of Christ" (2 Corinthians 10:5). Indeed, so fixed and irreformable is the doctrine that has been taught that the Galatians (1:8) are warned to anathematize any one, even an angel from heaven, who should preach to them a Gospel other than that which St. Paul had preached. Nor was this attitude — which is intelligible only on the supposition that the Apostolic College was infallible — peculiar to St. Paul. The other Apostles and apostolic writers were equally strong in anathematizing those who preached another Christianity than that which the Apostles had preached (cf. 2 Peter 2:1 sqq.; 1 John 4:1 sqq.; 2 John 7 sqq.; Jude 4); and St. Paul makes it clear that it was not to any personal or private views of his own that he claimed to make every understanding captive, but to the Gospel which Christ had delivered to the Apostolic body. When his own authority as an Apostle was challenged, his defense was that he had seen the risen Saviour and received his mission directly from Him, and that his Gospel was in complete agreement with that of the other Apostles (see, v.g., Galatians 2:2-9).
Finally, the consciousness of corporate infallibility is clearly signified in the expression used by the assembled Apostles in the decree of the Council of Jerusalem: "It hath seemed good to the Holy Ghost and to us, to lay no further burden upon you", etc. (Acts 15:28). It is true that the specific points here dealt with are chiefly disciplinary rather than dogmatic, and that no claim to infallibility is made in regard to purely disciplinary questions as such; but behind, and independent of, disciplinary details there was the broad and most important dogmatic question to be decided, whether Christians, according to Christ's teaching, were bound to observe the Old Law in its integrity, as orthodox Jews of the time observed it. This was the main issue at stake, and in deciding it the Apostles claimed to speak in the name and with the authority of the Holy Ghost. Would men who did not believe that Christ's promises assured them of an infallible Divine guidance have presumed to speak in this way? And could they, in so believing, have misunderstood the Master's meaning?
Proof from Tradition
If, during the early centuries, there was no explicit and formal discussion regarding ecclesiastical infallibility as such, yet the Church, in her corporate capacity, after the example of the Apostles at Jerusalem, always acted on the assumption that she was infallible in doctrinal matters and all the great orthodox teachers believed that she was so. Those who presumed, on whatever grounds, to contradict the Church's teaching were treated as representatives of Antichrist (cf. 1 John 2:18 sq.), and were excommunicated and anathematized.
It is clear from the letters of St. Ignatius of Antioch how intolerant he was of error, and how firmly convinced that the episcopal body was the Divinely ordained and Divinely guided organ of truth; nor can any student of early Christian literature deny that, where Divine guidance is claimed in doctrinal matters, infallibility is implied.
So intolerant of error was St. Polycarp that, as the story goes, when he met Marcion on the street in Rome, he did not hesitate to denounce the heretic to his face as "the firstborn of Satan". This incident, whether it be true or not, is at any rate thoroughly in keeping with the spirit of the age and such a spirit is incompatible with belief in a fallible Church.
St. Irenaeus, who in the disciplinary Paschal question favoured compromise for the sake of peace, took an altogether different attitude in the doctrinal controversy with the Gnostics; and the great principle on which he mainly relies in refuting the heretics is the principle of a living ecclesiastical authority for which he virtually claims infallibility. For example he says: "Where the Church is, there also is the Spirit of God, and where the Spirit of God is there is the Church, and every grace: for the Spirit is truth" (Adv. Haer. III, xxiv, 1); and again, Where the charismata of the Lord are given, there must we seek the truth, i.e. with those to whom belongs the ecclesiastical succession from the Apostles, and the unadulterated and incorruptible word. It is they who . . . are the guardians of our faith . . . and securely [sine periculo] expound the Scriptures to us" (op. cit., IV xxvi, 5).
Tertullian, writing from the Catholic standpoint, ridicules the suggestion that the universal teaching of the Church can be wrong: "Suppose now that all [the Churches] have erred . . . [This would mean that] the Holy Spirit has not watched over any of them so as to guide it into the truth, although He was sent by Christ, and asked from the Father for this very purpose — that He might be the teacher of truth" (doctor veritatis — "De Praescript", xxxvi, in P.L., II, 49).
St. Cyprian compares the Church to an incorruptible virgin: Adulterari non potest sponsa Christi, incorrupta est et pudica (De unitate eccl.).
It is needless to go on multiplying citations, since the broad fact is indisputable that in the ante-Nicene, no less than in the post-Nicene, period all orthodox Christians attributed to the corporate voice of the Church, speaking through the body of bishops in union with their head and centre, all the fullness of doctrinal authority which the Apostles themselves had possessed; and to question the infallibility of that authority would have been considered equivalent to questioning God's veracity and fidelity. It was for this reason that during the first three centuries the concurrent action of the bishops dispersed throughout the world proved to be effective in securing the condemnation and exclusion of certain heresies and maintaining Gospel truth in its purity; and when from the fourth century onwards it was found expedient to assemble ecumenical councils, after the example of the Apostles at Jerusalem, it was for the same reason that the doctrinal decision of these councils were held to be absolutely final and irreformable. Even the heretics, for the most part recognized this principle in theory; and if in fact they often refused to submit, they did so as a rule on the ground that this or that council was not really ecumenical, that it did not truly express the corporate voice of the Church, and was not, therefore, infallible. This will not be denied by anyone who is familiar with the history of the doctrinal controversies of the fourth and fifth centuries, and within the limits of this article we cannot do more than call attention to the broad conclusion in proof of which it would be easy to cite a great number of particular facts and testimonies.
Popes pronounce Infallible Dogmas very rarely. Pastor aeternus does not allow any infallibility for the Church or Pope for new doctrines. Any doctrines defined must be "conformable with Sacred Scripture and Apostolic Traditions". The reasons are obvious.
Thus not everything a Pope pronounces is infallible. There are limits set in place.
In the end I pray that some day, just some day we will all be of one faith and see the desire of Christ fulfilled on day he was arrested: That they all may be one!