There is one body and one Spirit, just as you were called to the 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 all.
Ephesians 4, 4-5
In Protestantism, any person who professes or has true faith in Christ is by this act a member of the Church that Christ founded regardless of which denomination they belong to. The Church is essentially pneumatic as an entire body of baptized believers. On the contrary, since ancient times, Catholics have acknowledged the Church which our Lord established as being a visible and hierarchical body consisting of no independent and completely autonomous denominations of disparate persuasions. It is not enough that a person is validly baptized to become a member of Christ’s body. Believers are removed or separated from this body by apostasy, heresy, schism, or ex-communication from the Catholic Church which is visibly one and apostolic since Pentecost. The idea that the Church is invisibly one in the Holy Spirit, though visibly divided in the world in matters pertaining to faith and morals, belongs to the Protestant paradigm.
Now you are Christ’s Body, and individually members of it. And God has appointed in the
Church, first apostles, second prophets, third teachers, then miracles, then gifts of healings,
helps, administrations, various kinds of tongues. All are not apostles, are they? All are not
prophets, are they? All are not teachers, are they? All are not workers of miracles, are they
All do not have gifts of healings, do they? All do not speak with tongues, do they? All do not
interpret, do they? But earnestly desire the greater gifts.
1 Corinthians 12, 27-31
St. Paul writes that the Mystical Body of Christ is a concrete unity no less than our own physical bodies are with its organized different members. One body presupposes a unified body, a whole comprised of many parts with different functions that all contribute to the maintenance of its proper state. Our Lord has composed this body so that there should be no division and disharmony within it. ‘And He [God the Father] put all things in subjection under His [Christ's] feet and gave Him as head over all things to the Church, which is His Body, the fullness of Him who fills all in all’ (Eph 1:22). Yet the Body of Christ is a plurality of members, each of whom has a different place and function in it. The members don’t all have the same function or role. Meanwhile, some spiritual gifts are greater than others, though all the members are equally dependent on each other to keep the body functioning properly.
Indeed, the one Body is hierarchically organized, each of the subordinate functions equally contributing to the unified and harmonious activity of the entire body. Christ is placed at the top of the hierarchy as the Head of the Body. The Head and members together form one Body consisting of one shared divine life. ‘Rather, speaking the truth in love, we are to grow up in every way into Him, who is the Head, Christ, from whom the whole body, joined and knit together by every joint with which it is supplied, when each part is working properly, causes the growth of the Body for the building up of itself in love’ (Eph 4:15-16).
The Holy Spirit is the life of the Body or its source of animation, the soul of the Church. The Holy Spirit is invisible, but the Church is not. The Church isn’t merely pneumatic but a composite of soul and body with all its members. And so, Paul writes: ‘For we were all baptized by one Spirit so as to form one body-whether Jews or Gentiles, slave or free-and we were all given the one Spirit to drink’ (1 Cor 12:13). The Holy Spirit is the life-principle of the Body of Christ, the source of Church unity in the oneness of faith. All members of the Body are in union with Christ by being incorporated into it through the Holy Spirit. If there is division or dissent in the Church, the Holy Spirit isn’t the cause. It's when one member of the Body desires to be more presentable than the other or to have more honor bestowed on it that dissension and division arise in the Church. It's like the Body has been invaded by a malignant virus from an outside source, that being the Devil.
When Paul tells us, “It is no longer I who live, but Christ lives in me,” (Gal 2:20) he is referring to our union with Christ in his Mystical Body which is the Church. We mustn’t understand his words in an individualistic ‘Jesus-and-me’ sense which lies at the root of a Protestant’s indifference to joining the Catholic Church. But our union with Christ in all its fullness and vitality is completed through our incorporation into his Mystical Body which is the one Church he founded on Peter the Rock so that all its members would be one in faith and share one baptism in common. Jesus says that a city set on a hill cannot be hidden. This city he is referring to is the Church (Mt 5:14).
The idea that the Church is an invisible, ethereal corporate entity united in the Holy Spirit, notwithstanding the countless self-governing Christian denominations that visibly exist with their fundamental differences of beliefs, doesn't comply with our Lord's vision and intention (Jn 17:11, 21, 23). Jesus gave Peter and the apostles the authority to bind and loose (Mt 16:19; 18:18). This ruling and teaching authority requires the Church to be hierarchical and thereby visibly united. Binding and loosing are visible acts in a Church where there is only one flock in accord with Jesus' design (Jn 10:16).
The gifts he gave were that some would be apostles, some prophets,
some evangelists, some pastors and teachers, to equip the saints for
the work of ministry, for building up the body of Christ,
Ephesians 4, 11-12
The Church that Christ founded is not only visibly united in its shared faith and celebration of the same sacraments, but also in its shared ecclesial hierarchy. Each of these has been received and passed down from the apostles whom our Lord invested with divine authority. Jesus is the invisible Head of the Body, which is the Church, while Peter is the visible head on earth. Each member of the visible hierarchy can be one in unity only if the visible hierarchy is ordered to its one visible head. Moreover, if the visible head of the hierarchy were plural, then the invisible hierarchy would not be essentially but only accidentally unified. In this case, the Church could not be infallible in its teachings, and all doctrines would be based on nothing more than popular opinion or agreeing to agree with each other. There could be no absolute certainty in the veracity of the Church’s teaching. In fact, there could be no reliable teaching authority in the Church.
The Robber Council which opposed the decisions reached by the Council of Ephesus in the 5th century demonstrates this unsustainable state of affairs. We have an equal number of bishops in each camp at loggerheads with each other. But the original council that convened in Ephesus (accepted today by both faithful Catholics and Eastern Orthodox) is the valid one since its declarations were ratified by the Pope in Rome. Since the bishops of the original council were united with Peter’s successor, the Church could be absolutely certain that the decisions which were made were immune to an error by the guaranty of the Holy Spirit just as it was in Jerusalem in apostolic time (Acts 15).
Hence, separate hierarchies present visible disunity in the Church, constituting a plurality of distinct authoritative entities that threaten the unity of faith. Who is to say which hierarchy can rightfully claim that it’s protected and guided by the Holy Spirit if there isn’t a visible head which has been ordered by Christ and graced with the charism of infallibility? This is the dilemma Protestants have faced from the time of Martin Luther and is the root cause of the splintering of Protestantism with its thousands of independent and autonomous denominations rising one after another. This isn’t the “building up of the body of Christ” but rather perpetually demolishing it if, in fact, Protestants are visible members but at doctrinal odds with one another. The invisible Holy Spirit cannot certainly be behind this mayhem.
Ironically, Protestants don’t believe that Christ founded one visible Church on one visible head, namely Peter, with whom the apostles had to be in union with for their teachings to be infallible or free from grave error by the guaranty of the Holy Spirit (Acts 15:1-35). Yet every single Protestant congregation has a head pastor. The Church is invisible, but each visible church is led and ruled by a visible head for the sake of unity in matters of faith and morals among its members. This inconsistency only confirms what the Catholic Church has regarded as essential for preserving Church unity since apostolic time. Without an essentially unified visible hierarchy ordered to one visible head, a composite whole cannot be a body nor even a visible one.
However, Christ intended his Church to be a composite whole and hierarchical visible body under one visible head who represents him. Our Lord knew in his wisdom that if one unified hierarchy weren’t in place or was abandoned at some point in history, nothing else could preserve unity in faith or unity of sacraments. Paul himself describes the Church as one visible body comprised of single members who form a visible hierarchy of believers. In the Protestant paradigm, we have one invisible body made up of separate visible bodies comprised of many visible hierarchies and members under different visible heads. It’s hard to believe that the one Spirit or soul animates what amounts to be an incomposite body which can be divided into countless separate bodies and heads. God is not the author of confusion but of peace (1 Cor 14:33). All the churches which the apostles and their successors founded belonged to the one visible Church with Peter as its one visible head on earth.
For just as we have many members in one body and all the members do
not have the same function, so we, who are many, are one Body in Christ,
and individually members one of another.
Being of one Spirit, one faith, and one baptism essentially requires one visible Church and doctrinal unity. All faithful Catholics, for instance, believe Mary is the Mother of God and practice infant baptism. This certainly isn’t the case in Protestantism or denominational Christianity. Jesus warned that the gates of hell would try to destroy the Church but wouldn’t prevail against it for the reason that our Lord would build his church on Peter the rock to whom he would give the keys of the kingdom (Mt 16:18). Satan initially tried to demolish the Church by trying to create doctrinal disunity. For instance, the New Testament church had to grapple with dissenting Christian sects such as the Docetists and Judaizers who opposed the apostolic teaching authority of the Church. These sects were responsible for dissension and discord among the church’s members.
Paul warned the faithful to avoid those who created all this disharmony by not listening to their teachings (Rom 16:17). While Paul was dealing mainly with the Judaizers, false teachers were a dangerous problem for the church to which John was writing. His warning against showing hospitality to false teachers (notably Docetists) may have sounded harsh and unchristian, yet these men were teaching Christological heresy that could seriously harm the faith of his flock (1 Jn 4). The NT was written to confirm what the apostles preached and taught in the Church to help dispel the confusion of mind and preserve doctrinal unity. The Apostolic Tradition had to be defended so that the Church would not become divided and eventually splinter into separate sects or denominations started by men with no apostolic authority invested in them by Christ.
Indeed, Paul exhorted the church in Philippi to stand firm in one spirit and with one mind striving together to uphold the true faith of the gospel (Phil 1:27). He urged the Thessalonians to stand firm and hold fast to the traditions or teachings they received from the apostolic authority (2 Thess 2:15). The apostle had much to fear and contend with, in the wake of false teachings which infiltrated the Church throughout many regions. He fervently prayed that all Christians be of the same mind in one accord (Phil 2:2). When Paul ordained Timothy as bishop, he warned of those who sought controversy and having disputes by challenging the common faith of believers. And he reminded him to safeguard and pass on the teachings that were handed down by the universal apostolic teaching authority of the Church (1 Tim 6; 2 Tim 2:2).
Paul acknowledged the Church to be the bride of Christ (Eph 5:25). One unified visible church means that our Lord has only one bride, not many brides. Likewise, Christ is the Head of one body, the Church, not countless bodies or denominations, each with their own visible head that disagrees with the others in some point of doctrine. Peter exhorted the faithful to have unity of spirit (1 Pet 3:8). He wouldn’t have made this charge if he didn’t acknowledge the Church to be one visible and hierarchical body. Unity of spirit and mind is impossible to achieve unless there is a central teaching authority established by Christ on the foundation of the apostles and their valid successors in the episcopate. And this apostolic teaching authority must be respected if there isn't to be any discord or even schism under the penalty of ex-communication (2 Cor 2:17; 3:6; 5:20; 10:6; 10:8; 1 Thess 5:12-13; 2 Thess 3:14; 1 Tim 5:17; Heb 13: 7, 17; 1 Pet 5:5; 2 Pet 2:10; 1 Cor 5:3-5; 16:22; 1 Tim 1:20; Gal 1;8; Mt 18:17). By apostolic succession, this divine office has continued and will continue under the guidance and protection of the Holy Spirit to ensure doctrinal unity until Christ returns in glory (Mt 28:16-20).
In his vision of the Church, Daniel prophesies that people of all nations and languages shall serve God’s kingdom (Dan 7:14). This single entity is the Catholic Church. The word catholic means universal in the sense that the Church consists of all peoples of different nations and languages who, despite the global demographics of its members and different cultures, possess one mind and one spirit in faith, notwithstanding any dissension, discord, or scandal that may arise within the Church through the power of darkness, but not to the extent of its destruction. The Catholic Church has existed for almost 2000 years, outlasting all historical empires that have existed until now, and shall always exist on earth with Christ as its Head until he returns in glory.
Early Sacred Tradition
“Those, therefore, who desert the preaching of the Church, call in question the knowledge of
the holy presbyters…It behooves us, therefore, to avoid their doctrines, and to take careful
heed lest we suffer any injury from them; but to flee to the Church, and be brought up in her
bosom, and be nourished with the Lord’s Scriptures. For the Church has been planted as a
garden (paradisus) in this world; therefore says the Spirit of God, ‘Thou mayest freely eat
from every tree of the garden,’ that is, Eat ye from every Scripture of the Lord; but ye shall
not eat with an uplifted mind, nor touch any heretical discord.”
St. Irenaeus, Against Heresies, 5:20
“Our Lord, whose precepts and admonitions we ought to observe, describing the honour of a
bishop and the order of His Church, speaks in the Gospel, and says to Peter: I say unto thee,
That thou art Peter, and upon this rock will I build my Church…Thence, through the changes
of times and successions, the ordering of bishops and the plan of the Church flow onwards; so
that the Church is founded upon the bishops, and every act of the Church is controlled by
these same rulers. Since this, then, is founded on the divine law, I marvel that some, with daring
temerity, have chosen to write to me as if they wrote in the name of the Church; when the
Church is established in the bishop and the clergy, and all who stand fast in the faith.”
St. Cyprian, To the Lasped, Epistle 26/33
“‘And in the last days the mountain of the house of the Lord shall be prepared on the top of
the mountains’ The house of the Lord, ‘prepared on the top of the mountains,’ is the church,
according to the declaration of the apostle, ‘Know,’ he says, ‘how thou oughtest to behave
thyself in the house of God, which is the church of the living God’ Whose foundations are on
the holy mountains, for it is built upon the foundation of the apostles and prophets. One also
of these mountains was Peter, upon which the rock the Lord promised to build his church.”
St. Basil, Commentary on Isaiah, 2:66
He that is not with me is against me:
and he that gathers not with me scatters.
Luke 11, 23