2. A Central Point of Disagreement. In the course of our discussions, it has become increasingly clear to us that the most divisive element in our traditions has been a growing diversity, since the late patristic centuries, in the ways we understand the structure of the Church itself, particularly our understanding of the forms of headship that seem essential to the Church’s being at the local, regional and worldwide levels. At the heart of our differences stands the way each of our traditions understands the proper exercise of primacy in the leadership of the Church, both within the various regions of the Christian world and within Christianity as a whole. In order to be the Body of Christ in its fullness — to be both “Orthodox” and “Catholic” — does a local community, gathered to celebrate the Eucharist, have to be united with the other Churches that share the Apostolic faith, not only through Scripture, doctrine, and tradition, but also through common worldwide structures of authority — particularly through the practice of a universal synodality in union with the bishop of Rome?
It seems to be no exaggeration, in fact, to say that the root obstacle preventing the Orthodox and Catholic Churches from growing steadily towards sacramental and practical unity has been, and continues to be, the role that the bishop of Rome plays in the worldwide Catholic communion. While for Catholics, maintaining communion in faith and sacraments with the bishop of Rome is considered a necessary criterion for being considered Church in the full sense, for Orthodox, as well as for Protestants, it is precisely the pope’s historic claims to authority in teaching and Church life that are most at variance with the image of the Church presented to us in the New Testament and in early Christian writings. In the carefully understated words of Pope John Paul II, “the Catholic Church’s conviction that in the ministry of the bishop of Rome she has preserved, in fidelity to the Apostolic Tradition and the faith of the Fathers, the visible sign and guarantor of unity, constitutes a difficulty for most other Christians, whose memory is marked by certain painful recollections” (Ut Unum Sint 88).
3. Divergent Histories. The historical roots of this difference in vision go back many centuries. Episcopal and regional structures of leadership have developed in different ways in the Churches of Christ, and are to some extent based on social and political expectations that reach back to early Christianity. In Christian antiquity, the primary reality of the local Church, centered in a city and bound by special concerns to the other Churches of the same province or region, served as the main model for Church unity. The bishop of a province’s metropolitan or capital city came to be recognized early as the one who presided at that province’s regular synods of bishops (see Apostolic Canon 34). Notwithstanding regional structural differences, a sense of shared faith and shared Apostolic origins, expressed in the shared Eucharist and in the mutual recognition of bishops, bound these local communities together in the consciousness of being one Church, while the community in each place saw itself as a full embodiment of the Church of the apostles.
In the Latin Church, a sense of the distinctive importance of the bishop of Rome, as the leading although not the sole spokesman for the apostolic tradition, goes back at least to the second century, and was expressed in a variety of ways. By the mid-fourth century, bishops of Rome began to intervene more explicitly in doctrinal and liturgical disputes in Italy and the Latin West, and through the seventh century took an increasingly influential, if geographically more distant, role in the Christological controversies that so sharply divided the Eastern Churches. It was only in the eleventh and twelfth centuries, during what is known as the Gregorian reforms, that the bishops of Rome, in response to centuries-old encroachments on the freedom and integrity of Church life by local secular rulers, began to assert the independence of a centrally-organized Catholic Church in a way that was to prove distinctive in Western society. Gradually, a vision of the Church of Christ as a universal, socially independent single body — parallel to the civil structure of the Empire, consisting of local or “particular” Churches, and held together by unity of faith and sacraments with the bishop of Rome — developed in Latin Christianity, and became, for the West, the normative scheme for imagining the Church as a whole.
Even in the Middle Ages, however, this centralized vision of the universal Church was not shared by the Orthodox Churches. In April, 1136, for instance, a Roman legate – the German bishop Anselm of Havelberg — visited Constantinople and engaged in a series of learned and irenic dialogues on issues dividing the Churches with the Byzantine Emperor’s representative, Archbishop Nicetas of Nicomedia. In the course of their conversations, Nicetas frequently expresses his love and respect for the Roman see, as having traditionally the “first place” among the three patriarchal sees – Rome, Alexandria and Antioch – that had been regarded, he says, since ancient times as “sisters.” Nicetas argues that the main scope of Rome’s authority among the other Churches was its right to receive appeals from other sees “in disputed cases,” in which “matters which were not covered by sure rules should be submitted to its judgment for decision” (Dialogues 3.7: PL 1217 D). Decisions of Western synods, however, which were then being held under papal sponsorship, were not, in Nicetas’s view, binding on the Eastern Churches. As Nicetas puts it, “Although we do not differ from the Roman Church in professing the same Catholic faith, still, because we do not attend councils with her in these times, how should we receive her decisions that have in fact been composed without our consent — indeed, without our awareness?” (ibid. 1219 B). For the Orthodox consciousness, even in the twelfth century, the particular authority traditionally attached to the see of Rome has to be contextualized in regular synodal practice that includes representatives of all the Churches.
By the mid-nineteenth century, the Western emphasis on the Church’s political and social autonomy had become a central feature of a distinctively Catholic ecclesiology. Reformation disputes about the nature of the Church’s institutions and the importance of ecclesial traditions had led Catholic theology to emphasize the Church’s institutional self-sufficiency in a way unprecedented in patristic thinking, and unparalleled in the Christian East. The challenges of the Western Enlightenment to religious faith, and the threats of the new secular, absolutist forms of civil government that developed in nineteenth-century Europe, challenged the competence and even the right of Catholic institutions to teach and care for their own people. In this context, the emphasis of the First Vatican Council’s document Pastor Aeternus (1870) on the Catholic Church’s ability to speak the truth about God’s self-revelation in a free and unapologetic way, and to find the criteria for judging and formulating that truth within its own tradition, can be understood as a reaffirmation of the apostolic vision of a Church called by Christ to teach and judge through its own structures (see, e.g., Matt 16:18; 18.15-20; Lk 10.16). Yet Vatican I’s way of formulating the authority of Catholic Church officials — particularly its definition of the Pope’s “true and proper primacy of jurisdiction” over each local Church and every Christian bishop (DS 3055, 3063), and its insistence that the Pope, “when acting in the office of shepherd and teacher of all Christians… possesses… that infallibility with which the divine Redeemer willed his Church to be endowed in defining doctrine” — shocked critics of the Catholic Church, and has remained since then a focus of debate and further interpretation within the Catholic world. Despite the attempt of the Second Vatican Council (Lumen Gentium 23-25 ) to contextualize and refine this portrait of papal authority and Church structure, the Catholic Church’s vision of a teaching authority and a practical decision-making power vested in the Pope, who faces few wider institutional checks, has been a principal cause of division between it and the Churches outside its communion.
In the Eastern world, structures of authority and community in the Church developed in a somewhat different pattern from the fourth century onwards. The bishop of Constantinople was recognized in 381 as “patriarch,” and second in order of precedence after the bishop of “the old Rome”; after the Council of Chalcedon (451), he exercised supra-metropolitan authority in the northern part of the Eastern Empire, and was responsible for Christian missionary efforts outside the imperial borders. His see, along with the patriarchates of Rome, Antioch, Alexandria and Jerusalem, was recognized in the legislation of the Emperor Justinian, in the sixth century, as forming a “pentarchy” of primatial leadership among all the Churches. But while the Western Church went on to develop its own institutional independence in late antiquity and the early Middle Ages under the headship of the bishop of Rome, the Eastern Churches remained fully integrated into the religious and political fabric of the late Roman Empire, even as the Empire’s territory dwindled under the domination of Arab and Turkish peoples. The Church’s main doctrinal definitions remained imperial law; maintaining Christian unity was an important imperial priority. And when the Eastern Roman Empire finally fell before the Turkish invaders in 1453, the Churches of the eastern patriarchates shared the political and social role of unifying and protecting the Christian minorities in lands dominated by a variety of Muslim rulers. In the Slavic territories to the north and east, new metropolitan sees and new patriarchates continued to develop after the fall of Constantinople, carrying out the mission of unifying newly converted Christian peoples, who largely shared the same geographical, linguistic and ethnic characteristics. Primacy had a less supra-national character than it had acquired in the Latin Church; what we presently call autocephaly — ecclesiastical independence correlative to the emerging nation-state — had become the underlying pattern for ecclesiastical organization.
Custom and habit, in all human societies, tend to become law. Structures that had come into being gradually, under the pressures of changing cultural and political conditions, came to be seen in both Eastern and Western Christianity as normative for the life of the Church. Yet precisely in our times, when centralized power is increasingly felt to be oppressive, and national identities and traditions are increasingly overwhelmed by the complexities of migration, mass communication, and supranational forces, questions continue to be raised about the enduring value of these structures. In our discussions, and indeed in discussions within our two Churches, such basic questions about the normativity of our current structures are inescapable.
4. What We Share. Despite disagreement on the place of the bishop of Rome in the worldwide cohesion of Christianity, however, it seems to us obvious that what we share, as Orthodox and Catholic Christians, significantly overshadows our differences. Both our Churches emphasize the continuity of apostolic teaching as the heart of our faith, received within the interpretive context of the historical Christian community. Both believe our life as Churches to be centered on the Divine Liturgy, and to be formed and nourished in each individual by the Word of God and the Church’s sacraments: baptism, the anointing with chrism, and the reception of the Eucharist mark, in each of our Churches, the entry of believers into the Body of Christ, while ordination by a bishop sets some of them apart for permanent sacramental ministry and leadership, and the marriage of a Christian man and woman within the liturgical community forms them into living signs of the union of Christ and the Church. Both our Churches recognize that “the Church of God exists where there is a community gathered together in the Eucharist, presided over, directly or through his presbyters, by a bishop legitimately ordained into the apostolic succession, teaching the faith received from the apostles, in communion with the other bishops and their Churches” (Joint International Dialogue, Ravenna Statement  18). Both our Churches, too, recognize the importance of various kinds of primacy, as the Ravenna statement further affirms: “Primacy at all levels is a practice firmly grounded in the canonical tradition of the Church,” even though “there are differences of understanding with regard to the manner in which it is to be exercised, and also with regard to its scriptural and theological foundations” (ibid. 43). Both our Churches venerate Mary, the Mother of God, as the foremost among those transformed by the grace of Christ’s redemption, and both also honor a whole range of holy men and women from every age, many of them common to our two traditions. Both our Churches cherish ancient practices that help the faithful grow in holiness, value personal asceticism and fasting, reverence sacred images, promote the monastic life, and set a high value on contemplative prayer. In all of these ways, our lives as Churches are enriched by the same spiritual resources. A significant degree of communion already exists between us.
5. A Matter of Urgency. In light of the divine gifts that we share, then, it seems all the more urgent to us that our Churches grow closer together, in ways that the men and women of our time can see. The fact that our two Christian families have been separated in some central points of theology and Church discipline for almost a thousand years, and as a result no longer share in the sacramental communion that bound us together during the first millennium, is not only a violation of the will of God, as expressed in the prayer of Jesus at the Last Supper that his disciples “may be one” (John 17.21), but is also a serious impediment to effective Christian engagement in the world, and to the effective realization of our common mission to preach the Gospel. Marriages involving members of both our traditions are increasingly common, especially in ethnically pluralistic countries, creating serious problems in Christian education and practice for the families involved. All of these factors urgently call our Churches to overcome their division. As our largely secular world reaches constantly for new technical means of communication, and for mutual understanding within all its cultural and political diversity, it is urgent that Orthodox and Catholic Christians find an effective way to realize our common tradition of faith together, and to present the world with a unified testimony to the Lordship of Jesus. To be what we are called to be, we need each other. In the words of the Second Vatican Council, “The divisions among Christians prevent the Church from realizing in practice the fullness of catholicity proper to her” (Unitatis Redintegratio 4). To become what we are, effectively and permanently, we cannot stop short of re-establishing full Eucharistic communion among ourselves. Clearly, this cannot be achieved without new, better harmonized structures of leadership on both sides: new conceptions of both synodality and primacy in the universal Church, new approaches to the way primacy and authority are exercised in both our communions.
6. The Shape of Communion. It is difficult to predict what a structure of worldwide ecclesial communion, sacramental and spiritual, between our Churches, might look like. Some of its main features, however, would include the following:
a) Mutual Recognition: the larger units of Orthodox and Catholic Christianity, including patriarchates and other autocephalous Churches, would explicitly recognize each other as authentic embodiments of the one Church of Christ, founded on the apostles. This would include the recognition of our fundamental agreement on central Christian dogmas, as revealed in Scripture and articulated in mutually recognized ecumenical Councils, despite variations in our theological and liturgical traditions.
b) A Common Confession of Faith: both our Churches would confess the same basic Christian faith, as expressed in the Christian canon of Scripture and in the Churches’ traditional creeds. The “faith of Nicaea,” professed by the ancient councils as the foundation of Christian faith and practice, is received most fully in the original form canonized at the Council of Constantinople in 381, as understood through the canons and prescriptions of the other ecumenical councils received by Orthodox and Catholic Christians. As we have suggested in our 2003 statement “The Filioque: a Church-Dividing Issue?” the original Greek form of the Creed of 381, because of its authority and antiquity, should be used as the common form of our confession in both our Churches.
c) Accepted Diversity: different parts of this single Body of Christ, drawing on their different histories and different cultural and spiritual traditions, would live in full ecclesial communion with each other without requiring any of the parts to forego its own traditions and practices (see Unitatis Redintegratio 16).
d) Liturgical Sharing: members of all the Churches in communion would be able to receive the sacraments in the other Churches; priests and bishops would express their unity in concelebration, and the heads of the other Churches would be commemorated liturgically in the diptychs. In addition, other forms of common liturgical prayer would be encouraged as a regular practice involving both our Churches.
e) Synodality/Conciliarity: the bishops of the reunited Churches would meet regularly in regional synods, which would regulate the common life and relationships of the Churches in a particular region and provide an occasion for mutual correction and support. Bishops of all the Churches would be invited to participate fully in any ecumenical councils that might be summoned. Synodality would operate at various levels of ecclesial institutions: local, regional and worldwide. Aside from episcopal structures of synodality, the laity would be active participants in this dimension of Church life.
f) Mission: all the Churches would share a common concern for what directly affects their unity, as well as for their mission to non-Christians. As sister Churches, they would also engage in common efforts to promote the realization of a Christian moral vision in the world.
g) Subsidiarity: following the ancient principle recognized as normative for well-organized human structures, “higher” instances of episcopal authority would only be expected to act when “lower” instances were unable to make and implement the decisions necessary for continuing union in faith. This would mean, among other things, that in the Orthodox and Eastern Catholic Churches, at least, bishops would be elected by local synods or by other traditional methods of selection. Those elected to major episcopal or primatial offices would present themselves to other Church leaders at their level, to their own patriarch, and to the bishop of Rome as first among the patriarchs, by the exchange and reception of letters of communion, according to ancient Christian custom. The bishop of Rome would also inform the Eastern patriarchs of his election.
h) Renewal and Reform. Ordered growth is essential to the health and well-being of the Church, and this means both continuity and change. For the Church, an essential aspect of this growth is renewal: the continual rediscovery of its fundamental identity as the Body of Christ, based on its experience of the Paschal Mystery, in the constant readiness to take on new forms of common life and witness and to adapt itself to new historical situations. In the words of a late medieval aphorism, “The Church is always in need of reform (ecclesia semper reformanda).” By making their catholicity concrete through full communion, the Catholic and Orthodox Churches would be realizing this life of reform in a new, undreamed-of way, and would be committing themselves to continuing renewal and growth – but now together. Life in communion with each other would be a life lived in readiness for a new Pentecost, in which people of many nations and cultures are formed anew by the living Word of God.
7. The Role of the Papacy. In such a communion of Churches, the role of the bishop of Rome would have to be carefully defined, both in continuity with the ancient structural principles of Christianity and in response to the need for a unified Christian message in the world of today. Although the details of that role would have to be worked out in a synodal way, and would require a genuine willingness on both sides to accommodate one another’s concerns, a few likely characteristics of this renewed Roman primacy would be these:
a) The bishop of Rome would be, by ancient custom, the “first” of the world’s bishops and of the regional patriarchs. His “primacy of honor” would mean, as it meant in the early Church, not simply honorific precedence but the authority to make real decisions, appropriate to the contexts in which he is acting. His relationship to the Eastern Churches and their bishops, however, would have to be substantially different from the relationship now accepted in the Latin Church. The present Eastern Catholic Churches would relate to the bishop of Rome in the same way as the present Orthodox Churches would. The leadership of the pope would always be realized by way of a serious and practical commitment to synodality and collegiality.
b) In accord with the teaching of both Vatican councils, the bishop of Rome would be understood by all as having authority only within a synodal/collegial context: as member as well as head of the college of bishops, as senior patriarch among the primates of the Churches, and as servant of universal communion. The “ordinary and immediate” jurisdiction of every bishop within his particular Church, would be “affirmed, strengthened and vindicated” by the exercise of the bishop of Rome’s ministry (Vatican II, Lumen Gentium 27; cf. Vatican I, Pastor Aeternus 3). In a reunited Church, this understanding of papal and episcopal authority, as complementary and mutually enhancing, would have to be expanded to include the much more complex patterns of local, primatial, and patriarchal leadership that have developed in the Eastern Churches since patristic times.
c) The fundamental worldwide ministry of the bishop of Rome would be to promote the communion of all the local Churches: to call on them to remain anchored in the unity of the Apostolic faith, and to observe the Church’s traditional canons. He would do this as a witness to the faith of Peter and Paul, a role inherited from his early predecessors who presided over the Church in that city where Peter and Paul gave their final witness.
d) His universal role would also be expressed in convoking and presiding over regular synods of patriarchs of all the Churches, and over ecumenical councils, when they should occur. In the Western Church, this same presiding function would include convoking and leading regular episcopal synods. In harmony with the Pope’s universal ecumenical ministry, the Roman curia’s relationship to local bishops and episcopal conferences in the Latin Church would become less centralized: bishops, for instance, would have more control over the agenda and the final documents of synods, and the selection of bishops would again normally become a local process.
e) In cases of conflict between bishops and their primates that cannot be resolved locally or regionally, the bishop of Rome would be expected to arrange for a juridical appeal process, perhaps to be implemented by local bishops, as provided for in canon 3 of the Synod of Sardica (343). In cases of dispute among primates, the bishop of Rome would be expected to mediate and to bring the crisis to brotherly resolution. And in crises of doctrine that might occasionally concern the whole Christian family, bishops throughout the world would have the right to appeal to him also for doctrinal guidance, much as Theodoret of Cyrus did to Pope Leo I in 449, during the controversy over the person of Christ that preceded the Council of Chalcedon (Ep. 113).
8. Preparatory Steps. To prepare for an eventual restoration of full communion within a reunited Church formed from the Orthodox and Catholic traditions, a number of steps might be helpful.
a) Delegations of Orthodox and Catholic bishops in a nation or region could begin to gather regularly for consultation on pastoral issues. Patriarchs and representatives of the autocephalous and autonomous Orthodox Churches could also meet with the Pope and leading Catholic bishops and curial officials on a regular basis for consultation and planning.
b) The Pope and the Orthodox primates could invite all the faithful under their jurisdiction to recognize each other’s Churches as “sister Churches” that fully realize the Apostolic faith in doctrine, sacraments and ecclesial life, despite the historically different forms in which our liturgy is celebrated, our doctrine taught, and our community life structured.
c) Special liturgical services and activities of common prayer and social ministry, involving lay people of both communions, could be organized as a way of drawing Orthodox and Catholic Christians into a deeper practical awareness of their common faith and dependence on God.
d) Ultimately, new structures of authority, in which the relationships of local and regional primates are concretely regulated, would need to be instituted by common consultation, perhaps by an ecumenical council.
9. Outstanding Questions and Problems. Confronted by these long-term prospects of growth towards ecclesial unity, we are aware that many serious theological, liturgical and structural questions remain unsolved, and need to be considered further. For example:
a) To what extent is the distinctive role of the pope rooted in the New Testament? How far is the role of Peter in the New Testament to be taken as setting out a pattern of leadership “inherited” by the bishops of Rome, whose Church rests on the ancient site of Peter’s martyrdom? While some of the Church Fathers present the Peter of Scripture as a model for all bishops, or even for the whole believing community, others – especially some fourth- and fifth-century bishops of Rome – have stressed the unique, even mystical connection between Peter and the later Popes who led Peter’s local Church. To what extent do these Scriptural interpretations simply reflect differing ecclesiologies?
b) What limits should be acknowledged, canonically and theologically, to the exercise of initiatives by the bishop of Rome in a universally reunited Church? What limits should be acknowledged to the authority and jurisdiction of the other patriarchs? Who has the authority to define these limits? To what extent can the formula of Apostolic Canon 34, from the late fourth century, serve as a model for the universal Church as well as for the local Churches: “The bishops of each national group should recognize the one who has first place among them, and consider him as head, and do nothing out of the ordinary without his agreement;… but neither should he do anything without the agreement of all”?
c) What kind of accountability can be canonically demanded of the bishop of Rome in his primatial role? What relevance does the ancient western principle used later by the defenders of papal authority, “the first see is to be judged by no one else,” have in today’s world of constitutionally regulated authority? What does the synodal or collegial dimension of papal authority imply for the Pope’s concrete exercise of his proper jurisdiction?
d) Can the bishop of Rome, as the one responsible for convening synods and councils of the universal Church, compel attendance and participation by representatives of particular Churches? Can he overrule those councils’ initiatives? Can he lay down rules of procedure?
e) What limits should be set to the common Orthodox practice of recognizing the autocephaly or autonomy of particular churches on ethnic, linguistic and geographical grounds? By what primatial and synodal authorities does such independence need to be recognized? Should diversity of national background continue to determine the structures of church life in a world that is increasingly shaped by the migration of peoples? What should the effect of today’s ethnic and cultural pluralism be on the unity and diversity of local Church organization, in countries representing the Orthodox “diaspora”? What aspects of the ancient principle of “one bishop, one place” can be reclaimed in contemporary society?
f) Beyond these technical questions, how much formal agreement on doctrine and Church structure is necessary before the Orthodox and Catholic Churches permit local communities to begin at least some degree of sacramental communion with each other? If diversity within our own Churches on theological issues is usually not seen as a barrier to Eucharistic sharing, should we allow the differences between Orthodox and Catholic Christians to overrule the substantial agreement our Churches already enjoy on most of the fundamental issues of faith, and keep us from receiving each other at the Eucharistic table, at least on some occasions? Would it be acceptable to both of our Churches to allow priests of one Church at least to care for the dying in the other, when no priest of their own is available? The extraordinary practice of shared communion has been carried on, at various critical points of recent history, in some parts of the world, and is occasionally carried on today. Can this serve as a precedent for wider Eucharistic sharing? Can such occasional sharing of communion serve as a concrete step towards deeper and more lasting unity?
10. One Body. In his Commentaryon the 17th Chapter of St. John’s Gospel,St. Cyril of Alexandria argues that the unity of the Church, modeled on the unity of Father and Son and realized through the gift of the Spirit, is primarily formed in us through the Eucharist in which the disciples of Jesus share:
For by liturgically blessing (eulogōn) those who believe in him into a single body – namely, his own – through sacramental participation, [Christ] has made them completely one body with himself and with each other. Who, after all, could divide, or alienate from natural unity with one another, those who are bound through the one holy body into unity with Christ? For if ‘all of us partake of the one loaf’ (1 Cor 10.17), all of us are formed into one body. It is impossible to divide Christ. That is the reason that the church is called the Body of Christ, and we are individually his members, as Paul understands it. For since we are all united with Christ through his holy Body – which we take, one and undivided, into our own bodies – we owe our own limbs more to him than to ourselves…
How, then are we all not clearly one [Cyril goes on to ask] in each other and in Christ? For Christ is himself the bond of unity, existing at the same time as God and as a human being…. And all of us who have received one and the same Spirit – I mean the Holy Spirit – are blended together, in a certain way, with each other and with God… For just as the power of his holy flesh forms those to whom it comes into a single body, in the same way, I believe, the one Spirit of God, who dwells in all of us undivided, brings us all to a spiritual unity (Comm. on John 11.11 [ed. Pusey 2.735-737]).
Conscience holds us back from celebrating our unity as complete in sacramental terms, until it is complete in faith, Church structure, and common action; but conscience also calls us to move beyond complacency in our divisions, in the power of the Spirit and in a longing for the fullness of Christ’s life-giving presence in our midst. The challenge and the invitation to Orthodox and Catholic Christians, who understand themselves to be members of Christ’s Body precisely by sharing in the Eucharistic gifts and participating in the transforming life of the Holy Spirit, is now to see Christ authentically present in each other, and to find in those structures of leadership that have shaped our communities through the centuries a force to move us beyond disunity, mistrust, and competition, and towards that oneness in his Body, that obedience to his Spirit, that will reveal us as his disciples before the world.