By unity is meant that the members of the true Church must be united in the belief of the same doctrines of revelation, and in the acknowledgement of the authority of the same pastors. Heresy and schism are opposed to Christian unity. By heresy, a man rejects one or more articles of the Christian faith. By schism, he spurns the authority of his spiritual superiors. That our Savior requires this unity of faith and government in His members is evident from various passages of Holy Writ. In His admirable prayer immediately before His passion He says: "I pray for them also who through their word shall believe in Me; that they all may be one, as Thou, Father, in Me and I in Thee, that they also may be one in Us; that the world may believe that Thou hast sent Me," [John xvii. 20, 21.] because the unity of the Church is the most luminous evidence of the Divine mission of Christ. Jesus prayed that His followers may be united in the bond of a common faith, as He and His Father are united in essence, and certainly the prayer of Jesus is always heard.
St. Paul ranks schism and heresy with the crimes of murder and idolatry, and he declares that the authors of sects shall not possess the Kingdom of God. [Gal. v. 20, 21.] He also addresses a letter to the Ephesians from his prison in Rome, and if the words of the Apostle should always command our homage, with how much reverence are they to be received when he writes in chains from the Imperial City! In this Epistle he insists upon unity of faith in the following emphatic language: "Be careful to keep the unity of the Spirit in the bond of peace; one body and one Spirit, as you are called in one hope of your calling; one Lord, one faith, one baptism, one God and Father of all, who is above all, and through all, and in us all." [Ephes. iv 3-6.] As you all, he says, worship one God, and not many gods; as you acknowledge the same Divine Mediator of redemption, and not many mediators; as you are sanctified by the same Divine Spirit, and not by many spirits; as you all hope for the same heaven, and not different heavens, so must you all profess the same faith.
Unity of government is not less essential to the Church of Christ than unity of doctrine. Our Divine Savior never speaks of His Churches, but of His Church. He does not say: "Upon this rock I will build my Churches," but "upon this rock I will build My Church," [Matt. xvi. 18.] from which words we must conclude that it never was His intention to establish or to sanction various conflicting denominations, but one corporate body, with all the members united under one visible Head; for as the Church is a visible body, it must have a visible head.
The Church is called a kingdom: "He shall reign over the house of Jacob forever, and of His kingdom there shall be no end." [Luke I. 32, 33.] Now in every well-regulated kingdom there is but one king, one form of government, one uniform body of laws, which all are obliged to observe. In like manner, in Christ's spiritual kingdom, there must be one Chief to whom all owe spiritual allegiance; one form of ecclesiastical government; one uniform body of laws which all Christians are bound to observe; for, "every kingdom divided against itself shall be made desolate." [Matt. xii. 25.]
Our Savior calls His Church a sheepfold. "And there shall be made one fold and one shepherd." [John x. 16.] What more beautiful or fitting illustration of unity can we have than that which is suggested by a sheepfold? All the sheep of a flock cling together. If they are momentarily separated, they are impatient till reunited. They follow in the same path. They feed on the same pastures. They obey the same shepherd, and fly from the voice of strangers. So did our Lord intend that all the sheep of His fold should be nourished by the same sacraments and the same bread of life; that they should follow the same rule of faith as their guide to heaven; that they should listen to the voice of one Chief Pastor, and that they should carefully shun false teachers.
His Church is compared to a human body. "As in one body we have many members, but all the members have not the same office; so we, being many, are one body in Christ, and every one members one of the other." [Rom. xii. 4, 5.] In one body there are many members, all inseparably connected with the head. The head commands and the foot instantly moves, the hand is raised and the lips open. Even so our Lord ordained that His Church, composed of many members, should be all united to one supreme visible Head, whom they are bound to obey.
The Church is compared to a vine. "I am the Vine, ye the branches; he that abideth in Me and I in him, the same beareth much fruit, for without Me ye can do nothing." [John xv. 5.] All the branches of a vine, though spreading far and wide, are necessarily connected with the main stem, and from its sap they are nourished. In like manner, our Savior will have all the saplings of His Vineyard connected with the main stem, and all draw their nourishment from the parent stock.
The Church, in fine, is called in Scripture by the beautiful title of bride or spouse of Christ [Apoc. xxi. 9.], and the Christian law admits only of one wife.
In fact, our common sense alone, apart from revelation, is sufficient to convince us that God could not be the author of various opposing systems of religion. God is essentially one. He is Truth itself. How could the God of truth affirm, for instance, to one body of Christians that there are three persons in God, and to another there is only one person in God? How could He say to one individual that Jesus Christ is God, and to another that He is only man. How can He tell me that the punishments of the wicked are eternal, and tell another that they are not eternal? One of these contradictory statements must be false. "God is not the God of dissension, but of peace." [I. Cor. xiv. 33.]
I see perfect harmony in the laws which govern the physical world that we inhabit. I see a marvelous unity in our planetary system. Each planet moves in its own sphere, and all are controlled by the central Sun.
Why should there not be also harmony and concord in that spiritual world, the Church of God, the grandest conception of His omnipotence, and the most bounteous manifestation of His goodness and love for mankind!
Hence, it is clear that Jesus Christ intended that His Church should have one common doctrine which all Christians are bound to believe, and one uniform government to which all should be loyally attached.
With all due respect for my dissenting brethren, truth compels me to say that this unity of doctrine and government is not to be found in the Protestant sects, taken collectively or separately. That the various Protestant denominations differ from one another not only in minor details, but in most essential principles of faith, is evident to every one conversant with the doctrines of the different Creeds. The multiplicity of sects in this country, with their mutual recriminations, is the scandal of Christianity, and the greatest obstacle to the conversion of the heathen. Not only does sect differ from sect, but each particular denomination is divided into two or more independent or conflicting branches.
In the State of North Carolina we have several Baptist denominations, each having its own distinctive appellation. There is also the Methodist Church North and the Methodist Church South. There was the Old and the New School Presbyterian Church. And even in the Episcopal Communion, which is the most conservative body outside the Catholic Church, there is ritualistic, or high church, and the low church. Nay, if you question closely the individual members composing any one fraction of these denominations, you will not rarely find them giving a contradictory view of their tenets of religion.
Protestants differ from one another not only in doctrine, but in the form of ecclesiastical government and discipline. The church of England acknowledges the reigning Sovereign as its Spiritual Head. Some denominations recognize Deacons, Priests, and Bishops as an essential part of their hierarchy; while the great majority of Protestants reject such titles altogether.
Where, then, shall we find this essential unity of faith and government? I answer, confidently, nowhere save in the Catholic Church.
The number of Catholics in the world is computed at three hundred millions. They have all "one Lord, one faith, one baptism," one creed. They receive the same sacraments, they worship at the same altar, and pay spiritual allegiance to one common Head. Should a Catholic be so unfortunate as contumaciously to deny a single article of faith, or withdraw from the communion of his legitimate pastors, he ceases to be a member of the Church, and is cut off like a withered branch. The Church had rather sever her right hand than allow any member to corrode her vitals. It was thus she excommunicated Henry VIII because he persisted in violating the sacred law of marriage, although she foresaw that the lustful monarch would involve a nation in his spiritual ruin. She anathematized, more recently, Dr. Döllinger, though the prestige of his name threatened to engender a schism in Germany. She says to her children: "You may espouse any political party you choose; with this I have no concern." But as soon as they trench on matters of faith she cries out: "Hitherto thou shalt come, and shalt go no farther; and here thou shalt break thy swelling waves" [Job xxviii. 12.] of discord. The temple of faith is the asylum of peace, concord and unity.
How sublime and consoling is the thought that whithersoever a Catholic goes over the broad world, whether he enters his Church in Pekin or in Melbourne, in London, or Dublin, or Paris, or Rome, or New York, or San Francisco, he is sure to hear the self-same doctrine preached, to assist at the same sacrifice, and to partake of the same sacraments.
This is not all. Her Creed is now identical with what it was in past ages. The same Gospel of peace that Jesus Christ preached on the Mount; the same doctrine that St. Peter preached at Antioch and Rome; St. Paul at Ephesus; St. John Chrysostom at Constantinople; St. Augustine in Hippo; St. Ambrose in Milan; St. Remigius in France; St. Boniface in Germany; St. Athanasius in Alexandria; the same doctrine that St. Patrick introduced into Ireland; that St. Augustine brought into England, and St. Pelagius into Scotland, and that Columbus brought to this American Continent, and this is the doctrine that is ever preached in the Catholic Church throughout the globe, from January till December--"Jesus Christ yesterday, and today, and the same forever." [Heb. xiii. 8.]
The same admirable unity that exists in matters of faith is also established in the government of the Church. All the members of the vast body of Catholic Christians are as intimately united to one visible Chief as the members of the human body are joined to the head. The faithful of each Parish are subject to their immediate Pastor. Each Pastor is subordinate to his Bishop, and each Bishop of Christendom acknowledges the jurisdiction of the Bishop of Rome, the successor of St. Peter, and Head of the Catholic Church.
But it may be asked, is not this unity of faith impaired by those doctrinal definitions which the Church has promulgated from time to time? We answer: No new dogma, unknown to the Apostles, not contained in the primitive Christian revelation, can be admitted. (John xiv. 26; xv. 15; xvi. 13.) For the Apostles received the whole deposit of God's word, according to the promise of our Lord: "When He shall come, the Spirit of truth, He shall teach you all truth." And so the Church proposes the doctrines of faith, such as came from the lips of Christ, and as the Holy Spirit taught them to the Apostles at the birth of the Christian law--doctrines which know neither variation nor decay.
Hence, whenever it has been defined that any point of doctrine pertained to the Catholic faith, it was always understood that this was equivalent to the declaration that the doctrine in question had been revealed to the Apostles, and had come down to us from them, either by Scripture or tradition. And as the acts of all the Councils, and the history of every definition of faith evidently show, it was never contended that a new revelation had been made, but every inquiry was directed to this one point--whether the doctrine in question was contained in the Sacred Scriptures or in the Apostolic traditions.
A revealed truth frequently has a very extensive scope, and is directed against error under its many changing forms. Nor is it necessary that those who receive this revelation in the first instance should be explicitly acquainted with its full import, or cognizant of all its bearings. Truth never changes; it is the same now, yesterday, and forever, in itself; but our relations towards truth may change, for that which is hidden from us today may become known to us tomorrow. "It often happens," says St. Augustine, "that when it becomes necessary to defend certain points of Catholic doctrine against the insidious attacks of heretics they are more carefully studied, they become more clearly understood, they are more earnestly indicated; and so the very questions raised by heretics give occasion to a more thorough knowledge of the subject in question." [De Civitate Dei, Lib. 16, Cap. ii., No. 1.]
Let us illustrate this. In the Apostolic revelation and preaching some truths might have been contained implicitly, e.g., in the doctrine that grace is necessary for every salutary work, it is implicitly asserted that the assistance of grace is required for the inception of every good and salutary work. This was denied by the semi-Pelagians, and their error was condemned by an explicit definition. And so in other matters, as the rising controversies or new errors gave occasion for it, there were more explicit declarations of what was formerly implicitly believed. In the doctrine of the supreme power of Peter, as the visible foundation of the Church, we have the implied assertion of many rights and duties which belong to the centre of unity. In the revelation of the super eminent dignity and purity of the Blessed Virgin there is implied her exemption from original sin, etc., etc.
So, too, in the beginning many truths might have been proposed somewhat obscurely or less clearly; they might have been less urgently insisted upon, because there was no heresy, no contrary teaching to render a more explicit declaration necessary. Now, a doctrine which is implicitly, less clearly, not so earnestly proposed, may be overlooked, misunderstood, called in question; consequently, it may happen that some articles are now universally believed in the Church, in regard to which doubts and controversies existed in former ages, even within the bosom of the Church. "Those who err in belief do but serve to bring out more clearly the soundness of those who believe rightly. For there are many things which lay hidden in the Scriptures, and when heretics were cut off they vexed the Church of God with disputes; then the hidden things were brought to light, and the will of God was made known." (St. Augustine on the 54th Psalm, No. 22.)
This kind of progress in faith we can and do admit; but the truth is not changed thereby. As Albertus Magnus says: "It would be more correct to style this the progress of the believer in the faith, than of the faith in the believer."
To show that this kind of progress is to be admitted only two things are to be proved: 1: That some divinely revealed truths should be contained in the Apostolic teaching implicitly, less clearly explained, less urgently pressed. And this can be denied only by those who hold that the Bible is the only rule of Faith, that it is clear in every part, and could be readily understood by all from the beginning. This point I shall consider farther on in this work. 2. That the Church can, in process of time, as occasions arise, declare, explain, urge. This is proved not only from the Scriptures and the Fathers, but even from the conduct of Protestants themselves, who often boast of the care and assiduity with which they "search the Scriptures," and study out their meaning, even now that so many Commentaries on the sacred Text have been published. And why? To obtain more light; to understand better what is revealed. It would appear from this that the only question which could arise on this point is, not about the possibility of arriving by degrees at a clearer understanding of the true sense of revelation, as circumstances may call for successive developments, but about the authority of the Church to propose and to determine that sense. So that, after all, we are always brought back to the only real point of division and dispute between those who are not Catholics and ourselves, namely, to the authority of the Church, of which I shall have more to say hereafter. I cannot conclude better than by quoting the words of St. Vincent of Lerins: "Let us take care that it be with us in matters of religion, which affect our souls, as it is with material bodies, which, as time goes on, pass through successive phases of growth and development and multiply their years, but yet remain always the same individual bodies as they were in the beginning. ... It very properly follows from the nature of things that, with a perfect agreement and consistency between the beginnings and the final results, when we reap the harvest of dogmatic truth which has sprung from the seeds of doctrine sown in the spring-time of the Church's existence, we should find no substantial difference between the grain which was first planted and that which we now gather. For though the germs of the early faith have in some respects been evolved in the course of time, and still receive nourishment and culture, yet nothing in them that is substantial can ever suffer change. The Church of Christ is a faithful and ever watchful guardian of the dogmas which have been committed to her charge. In this sacred deposit she changes nothing, she takes nothing from it, she adds nothing to it."