Every serious conversation between Catholics and Orthodox about reunion eventually arrives at the same question: the papacy. Not whether Peter held some kind of primacy—virtually no credible scholar on either side denies that—but whether that primacy was the kind of thing that creates a permanent office with jurisdiction that binds the universal Church. The First Vatican Council’s answer, codified in the dogmatic constitution Pastor Aeternus on July 18, 1870, remains the single most consequential point of division between the two communions. It is also the most misunderstood—by Catholics who have never read it, by Orthodox who have read only its critics, and by secularists who imagine it turned the pope into an oracle.

This article is not a defense of Pastor Aeternus from first principles—that work belongs to Article I, which examined the patristic evidence for Petrine primacy, and to Article II, which asked whether doctrine develops at all. Here the question is narrower and more precise: what did Vatican I actually define? What are the exact claims, the exact limits, and the exact scope of the authority the Council attributed to the Bishop of Rome? Only after those questions are answered can the Orthodox objection be engaged on its own terms—not as a caricature but as a serious theological challenge that deserves a serious theological response.

I. The Question This Article Answers

Both traditions read the same foundational texts. In Matthew 16:18–19, Christ says to Simon Peter: “You are Peter, and on this rock I will build my Church, and the gates of hell shall not prevail against it. I will give you the keys of the kingdom of heaven, and whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven.” In John 21:15–17, the risen Christ three times commands Peter to “feed my sheep.” In Luke 22:31–32, Christ tells Peter: “I have prayed for you that your faith may not fail; and when you have turned again, strengthen your brethren.”

The interpretive divide is not over whether these texts establish a Petrine role—they plainly do. The divide is over three further questions. First, is the Petrine commission personal to Simon Peter, or does it establish an office that passes to successors? Second, if it does pass to successors, does it confer jurisdiction (the authority to govern) or only a primacy of honor and pastoral coordination? Third, if it confers jurisdiction, is that jurisdiction ordinary and immediate over the whole Church, or is it limited to extraordinary intervention in cases of necessity?

The Catholic position, as defined by Pastor Aeternus, answers all three in the affirmative direction: the commission creates a permanent office, that office carries jurisdiction, and that jurisdiction is ordinary and immediate. The Orthodox position contests the second and third claims while increasingly acknowledging the first. This is the terrain of the debate—and it is considerably narrower than the popular perception on either side.

It is also worth noting what was not contested at Vatican I. No bishop at the Council denied that Rome held a genuine primacy. No bishop denied that Peter had been the chief of the apostles. The dispute was not over whether the pope possessed authority but over how to define its nature, its scope, and its relationship to the episcopate. The minority bishops who opposed the definition did not reject papal primacy—they questioned whether the moment was right and whether the formulation was balanced. That distinction matters enormously for understanding what happened in 1870.

II. The Historical Context: Why 1870?

Dogmatic definitions do not emerge in a vacuum. The Council of Nicaea defined the divinity of Christ in response to Arianism. The Council of Chalcedon defined the two natures of Christ in response to Monophysitism. The First Vatican Council defined papal authority in response to a convergence of pressures that made the question unavoidable—and the critics who point to these pressures are not wrong to do so. The question is whether political urgency invalidates theological truth, or whether Providence sometimes uses historical crises to compel the Church to articulate what it has always believed.

The most obvious pressure was the collapse of the Papal States. The Italian Risorgimento, the movement for Italian unification, had been steadily eroding the pope’s temporal sovereignty since the 1840s. By the time Vatican I convened in December 1869, the Papal States had already lost most of their territory. Pius IX knew—everyone knew—that Rome itself would soon fall. The definition of papal spiritual authority coincided almost exactly with the loss of papal temporal power: Pastor Aeternus was promulgated on July 18, 1870, and Italian troops entered Rome on September 20. The Council suspended indefinitely in October, never to reconvene.

The Orthodox and secular critique is straightforward: the definition was a compensatory claim. Having lost temporal sovereignty, the papacy grasped for spiritual supremacy as a substitute. There is enough historical truth in this observation to make it uncomfortable. Pius IX’s personal trajectory—from the liberal reformer of his early pontificate to the author of the Syllabus of Errors in 1864—does look like the journey of a man who felt the ground shifting beneath him and responded by fortifying the one kind of authority no army could take away.

The young Giovanni Maria Mastai-Ferretti had been elected pope in 1846 on a wave of liberal enthusiasm. He granted amnesty to political prisoners, established a civic guard, and relaxed press censorship in the Papal States. He was hailed as a reforming pope, the man who would reconcile the Church with the modern world. Then came 1848: revolution swept Europe, Pius IX’s own prime minister was assassinated on the steps of the Roman parliament, and the pope was forced to flee Rome in disguise. He returned in 1850 under the protection of French troops, and the liberal experiment was over. The Pius IX who convened Vatican I was not the man who had been elected twenty-three years earlier. He had concluded that liberalism was not a reform of Christendom but its dissolution, and that the Church needed to define its own authority clearly precisely because the world could no longer be relied upon to respect it.

This biographical context matters because it is the strongest version of the compensatory argument. The definition was not merely coincidental with the loss of temporal power—it was psychologically and politically continuous with it. But the compensatory reading, while partially illuminating, proves too much. If political motivation invalidates a council’s decrees, then Nicaea is equally compromised: Constantine convened it to restore imperial unity, not out of disinterested concern for Trinitarian theology. The Council of Chalcedon was entangled in the rivalry between Alexandria and Constantinople. The Second Council of Constantinople was convened under Justinian’s direct pressure. The question before any council is not whether political factors influenced the timing—they always do—but whether the definition itself is true.

The other major force at Vatican I was the ultramontane movement. Ultramontanism—literally, “beyond the mountains,” meaning beyond the Alps, toward Rome—was the theological and political movement that favored a strong, centralized papacy against both secular governments and local episcopal independence. Its leading voices included Louis Veuillot in France and W. G. Ward in England, and its intellectual energy had been building for decades. The ultramontanes wanted not just a definition of papal authority but the strongest possible definition: personal infallibility, universal jurisdiction, and freedom from any conciliar check.

Opposing them were the Gallicans and conciliarists—bishops who accepted papal primacy but insisted that it was limited by tradition, by the episcopate, and by the consent of the Church. The strongest voices in this camp included Félix Dupanloup, Bishop of Orléans; Josip Juraj Strossmayer, Bishop of Đakovo; Karl Josef von Hefele, the great historian of the councils; and Peter Richard Kenrick, Archbishop of St. Louis. These men were not opponents of the papacy. They were opponents of what they considered an imprudent and imbalanced formulation—and on several points, the final text of Pastor Aeternus actually reflects their concerns.

This sentence is the most important qualifier in the entire document. It was inserted precisely because the minority bishops insisted on it. The definition does not grant the pope the power to invent new doctrines—it binds him to the deposit of faith received from the apostles. The ultramontane maximalists wanted more; what they got was a definition that is simultaneously assertive about papal authority and restrictive about its scope. Both features must be read together, or the document is misunderstood.

III. What the Four Chapters Actually Define

The heart of Pastor Aeternus is four chapters, each concluding with a canon—a formal doctrinal statement to which the Council attaches an anathema. The chapters build on each other in a logical sequence: Chapter 1 establishes that Christ gave Peter a primacy of jurisdiction; Chapter 2 establishes that this primacy passes to Peter’s successors; Chapter 3 defines the nature of that jurisdiction; and Chapter 4 defines the conditions under which the pope teaches infallibly. Each chapter deserves careful examination.

Chapter 1: The Institution of the Apostolic Primacy in Blessed Peter

The first chapter is the foundation. It asserts that Christ conferred on Peter a primacy not merely of honor or precedence but of true and proper jurisdiction over the entire Church. The Council cites the three Petrine texts—Matthew 16:18–19, John 21:15–17, and Luke 22:31–32—and reads them as establishing an authority that is unique among the apostles, not reducible to a general apostolic commission shared equally by the Twelve.

The canon attached to Chapter 1 reads: “If anyone says that blessed Peter the Apostle was not appointed by Christ the Lord as prince of all the apostles and visible head of the whole Church militant; or that it was a primacy of honor only and not one of true and proper jurisdiction that he directly and immediately received from our Lord Jesus Christ himself: let him be anathema.”

This is the point where the Catholic and Orthodox readings diverge most sharply. The Orthodox tradition acknowledges Peter’s primacy but reads it as a primacy of honor—first among equals, not first above all. The Catholic reading insists that the distinction between honor and jurisdiction is present in the texts themselves: the power of the keys (Matthew 16:19) is a juridical metaphor, not a ceremonial one; the command to feed the sheep (John 21:15–17) is a pastoral commission, not an honorific title.

The honest assessment is that the Petrine texts are genuinely ambiguous on this precise point. Article I examined the patristic evidence in detail and found that the Fathers read these texts in multiple ways—sometimes emphasizing Peter’s person, sometimes his faith, sometimes his office. The Catholic case does not rest on a single proof-text but on the cumulative trajectory of how Rome actually exercised its primacy in the first millennium: intervening in disputes, receiving appeals, and acting as a court of final reference. Whether this trajectory constitutes development of a genuine apostolic deposit or innovation beyond it is the question Article II addressed.

Chapter 2: The Perpetuity of the Primacy in the Roman Pontiffs

If Chapter 1 establishes what Peter received, Chapter 2 establishes that it did not die with him. The primacy is not a personal charism attached to Simon Peter alone; it is an office that passes to his successors as Bishops of Rome. The Council declares that “what the prince of pastors and great shepherd of the sheep, Christ Jesus our Lord, established in the blessed Apostle Peter for the perpetual welfare and lasting good of the Church must, by the same institution, necessarily remain unceasingly in the Church.”

This is the structural claim—the one that converts the Petrine commission from a historical event into a permanent institution. Without this chapter, Pastor Aeternus would be an assertion about a first-century apostle, interesting but ecclesiologically inert. With it, the document claims that the Bishop of Rome stands in Peter’s place not by historical accident (Rome happened to be the imperial capital) or by conciliar decree (the councils assigned Rome a precedence it did not previously possess) but by divine institution: Christ willed that Peter have successors, and those successors sit in Rome.

Bessarion’s testimony is significant precisely because of who he was. Born in Trebizond, educated in the Platonic tradition, and ordained Metropolitan of Nicaea, he came to the Council of Florence as a member of the Greek delegation. He was not predisposed to accept the Roman position. But after months of patristic and conciliar debate, he concluded that the evidence favored Rome—and said so publicly, at considerable personal cost. He eventually became a cardinal, was twice nearly elected pope, and spent the rest of his life as a bridge figure between the two traditions. His full case belongs to a future revision of Article I, where the patristic evidence is examined at length. Here, his voice testifies to a simple but important fact: the strongest Orthodox scholars, when they have examined the primary sources with care, have not all reached the same conclusion.

The Orthodox alternative to Chapter 2 is that Rome’s primacy derives not from Petrine succession but from the city’s civil importance. Canon 28 of the Council of Chalcedon (451) assigned Constantinople privileges equal to those of Rome “because it is the new Rome,” implying that Rome’s status was civic rather than apostolic. The Catholic response, articulated by Pope Leo the Great’s legates at Chalcedon and reiterated by every subsequent pope, is that Canon 28 was never accepted by Rome precisely because it confused the basis of Roman primacy. Rome’s authority rests on the apostolic foundation of Peter and Paul, not on the political prestige of the imperial capital. If civil importance were the criterion, Rome should have lost its primacy when Constantinople became the effective seat of empire—and yet it did not. The Eastern churches continued to appeal to Rome, to seek Roman confirmation of their councils, and to treat the Bishop of Rome as the final court of appeal long after Rome ceased to be the political center of the Mediterranean world. This persistence is the historical argument for Chapter 2’s claim: the primacy survived the loss of civil importance because its foundation was never civil in the first place.

Chapter 3: The Power and Character of the Primacy of the Roman Pontiff

Chapter 3 is the most contested section of Pastor Aeternus—the place where the Orthodox objection lands hardest and the Catholic response must be most careful. It defines the jurisdiction of the Roman Pontiff as “ordinary and immediate,” extending over the whole Church in matters of faith, morals, discipline, and governance.

These are technical terms, and their misunderstanding has generated an enormous amount of unnecessary controversy. “Ordinary” does not mean “routine” or “everyday”—it means that the jurisdiction belongs to the office itself, not delegated from some higher authority. A diocesan bishop has ordinary jurisdiction over his diocese: it belongs to his office, not to a special mandate from Rome. In the same way, the pope has ordinary jurisdiction over the universal Church: it belongs to the office of Bishop of Rome by divine institution, not by delegation from a council or from the consent of the other bishops.

“Immediate” does not mean that the pope routinely intervenes in every diocese or overrides local bishops on daily matters. It means that the pope’s jurisdiction does not require any intermediary to be valid. He can, in principle, address any member of the faithful directly, without needing permission from the local bishop. This is the juridical basis for papal appeals—the practice, well documented in the first millennium, of individuals and local churches appealing directly to Rome for adjudication of disputes.

The document itself explicitly rejects the autocratic reading. Chapter 3 includes a passage that is almost never quoted by the Council’s critics: “This power of the Supreme Pontiff by no means detracts from that ordinary and immediate power of episcopal jurisdiction, by which bishops, who have succeeded to the place of the Apostles by appointment of the Holy Spirit, tend and govern individually the particular flocks which have been assigned to them. On the contrary, this power of theirs is asserted, strengthened, and defended by the supreme and universal pastor.”

There is no way to soften this language. It asserts a universal jurisdiction that is real, not ceremonial. The Catholic who wants to minimize Pastor Aeternus for ecumenical convenience is as wrong as the Orthodox critic who inflates it into an absolute monarchy. The claim is that the pope possesses genuine authority over the whole Church—but that this authority exists to serve the unity of the Church, not to replace the authority of its other shepherds. Whether this combination is coherent is precisely the theological question at stake.

Joseph Ratzinger, before he became Benedict XVI, offered one of the most careful formulations of how these authorities relate. In his Principles of Catholic Theology, he distinguished between the primacy as a “service of unity” and the primacy as a “claim of power.” The papacy, he argued, exists to guarantee that the communion of local churches remains a genuine communion—not a collection of autonomous bodies that agree to cooperate when convenient, but a single body with a visible center of unity that can act when communion is threatened. This is not the same as a CEO running a corporation. It is closer to the role of a judge in a constitutional system: someone whose authority exists to preserve the system itself, not to govern its every operation.

Chapter 4: The Infallible Teaching Authority of the Roman Pontiff

Chapter 4 is the most famous and most inflammatory section of Pastor Aeternus—the definition of papal infallibility. It is also, paradoxically, the most limited. The definition specifies four conditions that must all be met simultaneously for a papal teaching to qualify as an infallible exercise of the extraordinary magisterium:

The last clause—“of themselves, and not by the consent of the Church”—is the phrase that most disturbs Orthodox readers, and understandably so. It appears to sever the pope from the communion of the Church, making him a solitary oracle who can define doctrine without regard to the sensus fidelium, the consensus of bishops, or the witness of tradition. But the clause must be read in context. It was directed against a specific theological position—Gallicanism—which held that papal definitions required subsequent ratification by a council or by the whole episcopate to become binding. The Council was not saying that the pope operates in isolation from the Church; it was saying that his definitions do not require a separate act of ratification to take effect. The distinction is between requiring approval and requiring reception. A Supreme Court ruling does not need to be ratified by Congress to become binding law, but it does need to be grounded in the Constitution.

In practice, the restriction has proven remarkably effective. In the more than 150 years since Pastor Aeternus was promulgated, the charism of papal infallibility has been exercised exactly twice: the definition of the Immaculate Conception in 1854 (retroactively recognized as meeting the conditions once they were formally articulated) and the definition of the Assumption of Mary in 1950. Two definitions in a century and a half. Both concerned doctrines with deep roots in the tradition of the Church. Neither was a novelty; both articulated what the Church had long believed and practiced. The rarity is itself a datum: if the definition were really a blank check for papal absolutism, it would have been used far more often.

IV. Newman’s Letter to the Duke of Norfolk

No discussion of Pastor Aeternus is complete without John Henry Newman’s Letter to the Duke of Norfolk, written in 1875 in response to William Gladstone’s pamphlet The Vatican Decrees in Their Bearing on Civil Allegiance. Gladstone argued that the definitions of Vatican I made Catholics unfit for citizenship because they owed ultimate allegiance to a foreign sovereign who could command them to act against their own government and their own conscience. It was a serious charge, and Newman’s response is one of the most brilliant pieces of theological argumentation in the English language.

Newman accepted Pastor Aeternus without reservation—he had always believed in papal authority, and the definition confirmed rather than surprised him. But he also insisted, with characteristic precision, that the definition was self-limiting. The four conditions are so stringent, he argued, that they constitute a built-in check on papal power. The pope cannot teach infallibly on any subject he chooses; he is limited to faith and morals. He cannot teach infallibly in any venue he chooses; he must speak ex cathedra, in his capacity as universal pastor. He cannot define whatever he personally believes; he can only define what belongs to the apostolic deposit. The definition constrains as much as it empowers.

On the question of conscience, Newman offered what has become the most quoted sentence in all of Catholic apologetics on the papacy:

Newman’s genius was to show that Pastor Aeternus is, properly understood, a conservative document. It does not grant the pope unlimited power; it formalizes the limits on a power the Church has always believed the pope possessed. Before 1870, the nature of papal authority was debated among Catholics themselves: the Gallicans, the conciliarists, and the ultramontanes all offered different accounts. Pastor Aeternus settled the debate—and it settled it by rejecting the extremes on both sides. The Gallican position that papal definitions require conciliar ratification was excluded. But so was the ultramontane fantasy of a pope who could define whatever he wished, whenever he wished, on whatever subject he chose. What emerged was a carefully delimited authority: real but bounded, supreme but not arbitrary, universal but not totalitarian.

Newman is the ideal witness for this article’s argument because he embodies the Catholic synthesis. He was a convert from Anglicanism who came to believe in papal authority through the study of the Fathers and the development of doctrine—precisely the topics of Articles I and II. He was not an ultramontane enthusiast but a careful thinker who accepted the definition because he found it true, and then spent the rest of his life showing that its truth was compatible with intellectual freedom, with the rights of conscience, and with the proper authority of bishops. He is the model of the Catholic who holds the definition without holding the caricature.

What makes Newman’s Letter particularly valuable for the Catholic–Orthodox dialogue is his insistence on reading Pastor Aeternus in light of the whole tradition, not as an isolated decree. He argued that the definition must be interpreted minimally—that is, according to its strict terms, not according to the maximalist gloss that partisans on either side were eager to impose. The four conditions are the definition; everything beyond them is theological opinion, legitimately debated among Catholics. This principle of minimal interpretation is not a strategy for softening the definition but a hermeneutical rule rooted in the Church’s own conciliar tradition: councils mean what they say, not what their enthusiasts or their opponents wish they had said. Newman applied this principle rigorously, and the result was a reading of Vatican I that even its sharpest critics found difficult to dismiss.

Gladstone’s challenge, it should be noted, was not a marginal polemic. He was a four-time Prime Minister of Great Britain, and his pamphlet sold over 100,000 copies in its first weeks. The charge—that papal infallibility rendered Catholic citizens politically unreliable—was taken seriously across Protestant Europe. Newman’s response demolished the charge not by retreating from the definition but by showing that the definition itself contained the limits Gladstone claimed it lacked. The pope cannot command Catholics to act against the natural law, against the rights of conscience, or against the legitimate authority of civil government, because the charism of infallibility extends only to the deposit of faith—not to politics, not to science, not to military strategy. A pope who attempted to wield infallibility outside its defined scope would not be exercising the charism; he would be failing to meet its conditions. Newman made Gladstone’s argument self-defeating: the very definition Gladstone feared was the guarantee of the limits Gladstone demanded.

V. The Minority Bishops

The story of the minority at Vatican I is one of the most instructive chapters in the history of conciliar theology, and it is regularly misused by both sides. Critics of Pastor Aeternus point to the minority as evidence that the definition was contested from within and therefore lacks the unanimity that a genuine ecumenical council requires. Defenders sometimes minimize the minority as a handful of malcontents who were overruled by the Holy Spirit. Neither account is accurate.

The minority numbered roughly 60 to 80 bishops out of more than 700—a significant fraction, though clearly not a majority. Their leaders were men of formidable intellect and unquestioned orthodoxy. Félix Dupanloup, Bishop of Orléans, was one of the most celebrated preachers and educators in France, a man whose Catholic credentials were beyond challenge. Josip Juraj Strossmayer, Bishop of Đakovo in Croatia, was a passionate advocate for Slavic Catholics and a scholar of the Eastern tradition. Karl Josef von Hefele, Bishop of Rottenburg, was the author of the definitive history of the ecumenical councils—a man who knew the conciliar tradition better than anyone alive. Peter Richard Kenrick, Archbishop of St. Louis, was the highest-ranking American prelate to oppose the definition.

What united these men was not opposition to papal primacy but opposition to the timing and formulation of the infallibility definition. They raised several objections that deserve enumeration. First, the definition was inopportune: it would alienate Protestants, further divide Catholics from Orthodox, and provoke secular governments into anti-Catholic legislation. Second, the formulation was imbalanced: it defined papal authority without simultaneously defining the authority of bishops, creating a lopsided ecclesiology. Third, the historical evidence was contested: Hefele in particular argued that the case of Pope Honorius I, who was condemned for heresy by the Third Council of Constantinople in 681, posed a genuine difficulty for the claim of papal infallibility.

The Honorius question deserves a brief treatment because it remains the most cited historical objection to papal infallibility. Honorius, who reigned from 625 to 638, wrote two letters to Patriarch Sergius of Constantinople in which he appeared to endorse the Monothelite heresy—the position that Christ had only one will. The Third Council of Constantinople (680–681) condemned Honorius by name, and subsequent popes confirmed that condemnation. The Catholic response, developed in detail by theologians from Bellarmine to Newman, distinguishes between heresy in a pope’s personal theological opinions and heresy in an ex cathedra definition. Honorius never issued a solemn definition of Monothelitism. He wrote private letters that were theologically careless and pastorally negligent, but he did not invoke the fullness of his apostolic authority to bind the whole Church to a false doctrine. The Honorius case is, on Catholic terms, evidence that popes can err as private theologians—something no Catholic denies—but not evidence that the charism of infallibility as defined by Pastor Aeternus has ever failed. Whether this distinction satisfies is a judgment each reader must make; but it must at least be understood before it is rejected.

The minority’s concerns were not trivial, and the Council’s process reflected their influence. Several key qualifications in the final text—including the critical passage about the pope being bound to the deposit of faith—were inserted to address their objections. The definition that emerged was not the maximalist text the ultramontanes originally proposed; it was a compromise that preserved the substance of the claim while restricting its scope.

On the day of the final vote, July 18, 1870, the minority bishops chose to absent themselves rather than vote non placet against a definition that the overwhelming majority had approved. This was a deliberate and principled decision: they had made their case, they had lost, and they chose not to create a public spectacle of dissent. The final vote was 533 in favor, 2 against. Crucially, every minority bishop eventually submitted to the definition. Hefele was the last holdout, but even he accepted Pastor Aeternus within a year. None joined the Old Catholic schism that broke away from Rome over the definition.

The submission of the minority is theologically significant. It does not prove that they were wrong to raise their objections—the Church has always recognized the legitimacy of conciliar debate, and some of their concerns were vindicated when Vatican II promulgated Lumen Gentium in 1964, finally defining the theology of episcopal collegiality that Vatican I had left unfinished. What their submission demonstrates is that they accepted the conciliar process as authoritative even when they disagreed with the outcome. They believed that the Holy Spirit guides ecumenical councils, and they acted on that belief. The minority bishops are not evidence against Pastor Aeternus; they are evidence that the Catholic system of authority, including the authority of councils, was strong enough to accommodate genuine dissent and resolve it without schism.

VI. How Orthodox Theologians Have Engaged Pastor Aeternus

The Orthodox response to Pastor Aeternus has not been monolithic. It ranges from outright rejection to careful critical engagement to surprising concessions. The five theologians examined here represent the most serious Orthodox scholarship on papal authority in the twentieth century. None of them is a mere polemicist; all of them wrote with genuine learning and, in most cases, genuine respect for the Catholic tradition they were critiquing. They deserve to be engaged at their best, not at their weakest.

Nicholas Afanasiev (1893–1966) developed what he called “eucharistic ecclesiology”—the idea that the local church gathered around its bishop and celebrating the Eucharist is the Church in its fullness, not a branch office of a universal organization. If every local church is the complete Body of Christ, then universal jurisdiction is not just unnecessary; it is ecclesiologically impossible. There is no “super-church” above the local churches that could exercise authority over them. Rome presides in love—a phrase from Ignatius of Antioch’s letter to the Romans—but presiding in love is categorically different from ruling by jurisdiction.

The Catholic response to Afanasiev is twofold. First, his eucharistic ecclesiology was substantially adopted by the Second Vatican Council. Lumen Gentium §26 teaches that the Eucharist makes the Church present in each local community—language that clearly echoes Afanasiev. But the Council held this truth alongside the truth of universal primacy, not in opposition to it. The local church is genuinely the Church, but the communion of local churches requires a visible principle of unity at the universal level. Second, the sharp dichotomy between love and jurisdiction is less stable than it appears. Does a father who exercises authority over his family cease to act in love? Does a bishop who governs his diocese rule by power rather than service? Authority and love are not contraries; the question is whether they can coexist, and the Catholic tradition insists that they must.

John Zizioulas (1931–2023) advanced a communion ecclesiology that is more nuanced than Afanasiev’s and, in some ways, closer to the Catholic position. Zizioulas accepted that primacy is necessary at every level of the Church’s life—local, regional, and universal. He even accepted that the Bishop of Rome holds the primacy at the universal level. What he denied is that this primacy can take the form of jurisdiction, because jurisdiction implies power over the communion rather than service within it. The primate is constituted by the communion and cannot stand above it.

The Catholic response engages Zizioulas on his own terms. Pastor Aeternus Chapter 3 defines jurisdiction precisely as a service to communion, not a replacement for it. The passage stating that papal authority “strengthens and protects” episcopal authority is directly relevant: it defines the primacy as ordered toward the good of the communion, not toward its subjugation. Ratzinger’s work on primacy and communion, particularly in Principles of Catholic Theology and in his 1998 essay “The Primacy of the Successor of Peter in the Mystery of the Church,” argues that jurisdiction and communion are not opposed: jurisdiction is the juridical form that the service of communion takes when communion is threatened. A communion without any mechanism for resolving disputes is not a higher form of communion; it is a communion that has disarmed itself against its own fragmentation.

John Meyendorff (1926–1992) was arguably the most historically honest of the major Orthodox theologians on the question of Roman primacy. He did not deny that Rome exercised a genuine primacy in the first millennium—a concession that already undermines the “mere honor” position. He acknowledged that popes intervened in Eastern affairs, received appeals, and acted as arbiters in disputes. What he contested was the trajectory: he argued that Pastor Aeternus represents a “hyper-development” that went beyond the evidence, transforming a pastoral primacy into a juridical supremacy.

The Catholic response to Meyendorff is to take his honesty seriously and then turn it back on the “mere honor” position. If Rome’s primacy in the first millennium was real and not merely ceremonial—if popes actually did things that only someone with genuine authority could do—then the question becomes one of degree, not of kind. Was the development from first-millennium primacy to Pastor Aeternus organic or discontinuous? This is precisely the question Article II addressed, and the answer depends on one’s theory of doctrinal development. Meyendorff’s own concession that the primacy was real makes it harder, not easier, to draw a bright line between the ancient practice and the modern definition.

Kallistos Ware (1934–2022) was the most widely read Orthodox theologian in the English-speaking world, and his trajectory over five decades of writing is itself a datum in the debate. In his early work, he presented the Orthodox position on the papacy in fairly conventional terms: Rome holds a primacy of honor, not of jurisdiction. By his later work, he had moved considerably closer to accepting some form of universal primacy with real authority—not the jurisdiction defined by Pastor Aeternus, but something more than empty ceremony. His intellectual journey suggests that the primacy question is not closed even within Orthodoxy, and that the strongest Orthodox minds have found the “mere honor” position increasingly difficult to sustain.

The Catholic response to Ware is not to claim him as a crypto-Catholic but to note that his evolution illustrates a genuine theological problem. If the Church at the universal level needs a primate with real authority—and Ware increasingly conceded that it does—then the question is what form that authority should take. The Catholic position is that Pastor Aeternus answers that question. The Orthodox position is that it over-answers it. But the gap between “real authority” and “jurisdiction” may be narrower than the vocabulary suggests.

Alexander Schmemann (1921–1983) approached the question of Church structure from a liturgical perspective, and his work opens an unexpected angle on the primacy debate. If presiding at the Eucharist is not merely functional but iconographic—if the bishop at the altar is an image of Christ’s headship—then structure and worship are not separate categories. Both traditions embed a structural primacy in their liturgical life: the Roman Canon names the pope; Orthodox liturgies name the patriarch. Both traditions pray for their respective heads at the most solemn moment of their worship. This is not merely a disciplinary convention; it is a liturgical confession that the Church has a visible head whose authority is woven into the fabric of its worship.

The Catholic observation is simple: if the Eucharist reveals the Church’s structure, and if both traditions structure their Eucharistic prayer around a primate, then the question is not whether universal primacy exists but what it entails. Schmemann’s liturgical theology, taken to its logical conclusion, supports the existence of a structural primacy that is more than honorary—precisely the Catholic claim.

VII. Counter-Responses

VIII. Where the Question Leads

Pastor Aeternus does not close the debate between Catholics and Orthodox. It sharpens it. The real question is not whether the definition went “too far” in some vague sense but whether there exists a principled criterion for determining how far is too far. Article II of this series argued that doctrines develop—that the Church’s understanding of the apostolic deposit grows in precision and clarity over time, guided by the Holy Spirit. If that principle is granted, then Pastor Aeternus must be evaluated as a development: is it continuous with what came before, or is it a break? The Orthodox position is that it is a break. The Catholic position is that it is the same primacy the Fathers recognized, articulated with the precision that the circumstances demanded.

There is genuine common ground, and it should not be minimized. The 2007 Ravenna Document, produced by the Joint International Commission for Theological Dialogue between the Catholic and Orthodox Churches, agreed that primacy exists at every level of the Church’s life—local, regional, and universal—and that this primacy is not merely administrative but has a theological foundation. The Moscow Patriarchate walked out of the Ravenna session over the participation of the Estonian Apostolic Orthodox Church, which itself illustrates the structural problem the Catholic side identifies: without a primate who can adjudicate such disputes, even a dialogue about primacy can be derailed by the absence of primacy.