An Ecumenical Breakthrough | One Body

Sr. Donna Geernaert, SC

Monday, May 4, 2026

Stone-walled chapel interior with three small altars draped in white cloth, a vase of flowers, and a Sacred Heart image; an arched doorway and multilingual inscriptions appear on the walls.

Assyrian Church of Mar Toma, Mavana, Iran. Wikimedia Commons.

An Ecumenical Breakthrough

by Sr. Donna Geernaert, SC

On July 20, 2001, the Pontifical Council for Promoting Christian Unity (PCPCU) published its Guidelines for Admission to the Eucharist between the Chaldean Church and the Assyrian Church of the East. These Guidelines open the way for competent authorities in the Chaldean Catholic Church and the Assyrian Church of the East to establish procedures and provide appropriate means for the Chaldean and Assyrian faithful to receive the Eucharist of either Church under specific circumstances in cases of pastoral necessity. The principal issue for the Catholic Church in approving the decree related to the question of the validity of the Eucharist when celebrated with the Anaphora (or Eucharistic Prayer) of Addai and Mari which lacks a literal recitation of the Institution Narrative, Jesus’ words: “This is my Body, This is my Blood.” After careful study, the validity of this Anaphora was recognized by the Congregation of the Doctrine of the Faith (CDF) on January 17th 2001. Subsequently approved by Pope John Paul II, this has been recognized as an audacious decision: Robert Taft, SJ, an Archimandrite in the Ukrainian Catholic Church and a consultant for the Vatican Congregation for the Oriental Churches, has called the publication of the Guidelines “the most remarkable Catholic magisterial document since Vatican II.”

Sister Churches

The Acts of the Apostles names “residents from Mesopotamia” (contemporary Iraq) among the crowd gathered on the day of Pentecost (2:9). These were probably among the first Christians in Persia, where, according to tradition, the Apostle Thomas and his disciples Addai and Mari spread the Gospel and laid the foundations of the Assyrian Church of the East . Confined to the Persian Empire, this Church developed an original spiritual and theological tradition in a predominantly Semitic and East Syriac cultural context. In the 5th century, they gravitated towards the christology of the monk, Nestorius, whose focus on maintaining the humanity of Jesus led to a stress on the separation of human and divine natures in Christ who is not identical but personally united to the Word of God. Condemned at the Council of Ephesus (431 AD) with its declaration of Mary as theotokos (“Mother of God”), his followers fell out of communion with the church of the Roman Empire. In spite of its seclusion, the Assyrian Church developed an extraordinary missionary dynamism, following various silk routes through Central Asia, India and China. Beginning in 1553, successive bishops and their followers entered into communion with the See of Rome, forming the Chaldean Catholic Church Both churches share the same spiritual, theological, and liturgical traditions. Since their origins, the history of these two churches has been marked by persecution, forcing many of their members to emigrate to the West, taking their centuries-old traditions with them.

A Developing Dialogue

Theological dialogue between the Catholic Church and the Assyrian Church of the East began in 1984, with unofficial conversations promoted by the Pro Oriente Foundation in Vienna. These initial conversations enabled Pope John Paul II and Catholicos-Patriarch Mar Dinkha IV to sign a historic Common Christological Declaration in Rome on November 11, 1994, allowing them to “proclaim together before the world their common faith in the mystery of the Incarnation.” Putting an end to a doctrinal controversy which had lasted since the Council of Ephesus, the Common Declaration also established a Joint Commission for Theological Dialogue between the Catholic Church and the Assyrian Church of the East, which has met annually since 1995. In 2024, the Vatican published a commemorative book which brings together the documents that have marked the 30 year history of dialogue since the 1994 Common Christological Declaration.

Learn More:
Introducing the Pre-Chalcedonian Churches | Sr. Donna Geernaert, SC
Sr. Donna tells the encouraging story of renewed Catholic dialogue with Pre-Chalcedonian Churches: Oriental Orthodoxy and the Assyrian Church of the East.

Who are the Christians of Iraq? | Michael J.L. La Civita
Christians have been in Iraq since the 1st century and belong to a variety of traditions. CNEWA's Michael La Civita introduces us to them.

A Doctrinal Challenge

Promulgated on October 26, 2001 as an ecumenical response to a pastoral concern, the Guidelines also appear to challenge Catholic teaching on the importance of the words of institution in the Eucharistic consecration. Since approval of the Guidelines means that Catholics who participate in an Assyrian Eucharist using the Anaphora of Addai and Mari are attending a valid liturgical celebration as at a Catholic Eucharist, there are clear doctrinal implications: since the late Middle Ages, Catholic tradition has typically considered the words of institution to be essential to the validity of the Eucharistic Prayer. Faced with explaining how the Catholic Church can authorize its faithful to receive the Eucharist at a liturgy lacking the words of institution, the PCPCU, in collaboration with the CDF and the Congregation for the Oriental Churches published an accompanying article, “Admission to the Eucharist in Situations of Pastoral Necessity,” in L’Osservatore Romano, on November 14, 2001.

Further clarification was given by Fr. Taft in a lecture given at the Fifth annual Paul Wattson Conference at the Centro Pro Unione on March 20, 2003.

As it is intended to clarify the context, content, and practical application of the Guidelines, the L’Osservatore Romano article is essentially a commentary on them. It elaborates on the three major theological arguments offered in the Guidelines for recognizing the validity of the Anaphora of Addai and Mari:

The Anaphora is one of the most ancient Eucharistic prayers. Dating back to the time of the very early Church, it was composed and used with the clear intention of celebrating the Eucharist in continuity with the Last Supper, in obedience to the command of the Lord, and according to the intention of the Church. While the absence of a coherent Institution narrative is an exception in relation to Roman and Byzantine traditions developed in the 4th and 5th centuries, the validity of this Anaphora was never officially questioned in either East or West. Further, when parts of the Assyrian Church united with Rome between the 16th and 18th centuries, no document exists to prove that there was any insistence on the insertion of an Institution narrative into the Anaphora of Addai and Mari.

The Catholic Church recognizes the Assyrian Church of the East as a true particular Church, built upon orthodox faith and apostolic succession. Thus, in accord with Vatican II’s Decree on Ecumenism, this church has retained: “true sacraments, and above all by apostolic succession, the priesthood and the Eucharist” (Unitatis Redintegratio #15). Acknowledging that the Assyrian Church has preserved full Eucharistic faith in the real presence of Jesus under the species of bread and wine, and in the sacrificial character of the Eucharist, the response of the Catholic Church to the question of the validity of the Anaphora could only be positive. In brief, to say that the principal Anaphora used in this Church since time immemorial was invalid would be highly illogical.

The words of the Eucharistic Institution are indeed present in the Anaphora, not in a coherent literal way but rather in a dispersed way through prayers of thanksgiving, praise, and intercession.

In his Paul Wattson Conference lecture, Fr. Taft offered more detail on each of the above three points. His reflections on ecumenical scholarship and on the question of a missing Institution narrative are of particular interest. “Ecumenical scholarship,” he maintains, “is a specifically Christian way to study the Christian tradition in order to reconcile and unite rather than to confute and dominate…It is a contest of love, one in which the parties seek to understand and justify not their own point of view, but that of their interlocutor.” With regard to the question of the Institution narrative, he notes that “doctrinal formulations produced in the heat of polemics must be construed narrowly in relation to the errors they were meant to confute.” So, when the Council of Trent identifies the bread and wine becoming the body and blood of Christ through the consecration, “it was combatting those who denied the transformation, not making a statement about its ‘moment’ or ‘formula.’” He goes on to show how “Catholic teaching for over a century has been moving towards recovery of the view that what an earlier theology saw as the form of the Eucharist is the central prayer of the ritual, not a single isolated formula within that prayer. The words of institution are not a magical formula, but part of a prayer of the Church, operative within its worship context.” This does not deny that the words of Jesus are consecratory. In fact, their consecratory power comes not because of the priest’s liturgical repetition of them but because they are the words of Jesus, which are effective for all time. The words of Jesus “are also consecratory in the Anaphora of Addai and Mari, even though that ancient prayer does not have the priest repeat them verbatim,” but “adverts to them more obliquely.”

Implications

The publication of a commemorative volume marking the history of its dialogue with the Assyrian Church is a clear indication of the Vatican’s high regard for this developing relationship. A deepening “dialogue of love” is evident in the multiple meetings which have taken place between popes and patriarchs, concluding with Pope Francis' telling Patriarch Awa of his dream “that the separation with the beloved Assyrian Church of the East, the longest in the history of the Church, can also be, please God, the first to be resolved.”

An indication of growth in the “dialogue of life” is clearly evident on the local level in Iraq. In 1996, Patriarchs of the Chaldean Church and the Assyrian Church signed a Joint Patriarchal Statement that committed their two churches to working towards full ecclesial unity. For example, it pledged cooperation on pastoral questions such as drafting a common catechism, setting up a common seminary in the US, preservation of the Aramaic language, and other pastoral programs. In 1997, the two Patriarchs met again and ratified a “Joint Synodal Decree for Promoting Unity” that had been signed by members of both Synods. It restated the areas of agreement envisioned in the earlier joint statement, established an Assyrian-Chaldean “Joint Commission for Unity,” and stated that each side recognized the apostolic succession, sacraments, and Christian witness of the other. (Introduction, p. 15)

Within the Catholic community, the recognition of the validity of the Anaphora of Addai and Mari could have some interesting practical implications, particularly in the areas of ecumenical theology, and in a return to the earlier understanding that the consecration of the bread and wine occurs during the whole eucharistic prayer.

In the first place, ecumenical scholarship invites its advocates to avoid premature judgement and to take account of the entire history of one’s tradition, rather than just on the most recent aspects of that tradition which may have been narrowed by polemics. Further, the call to hear the voices of ecumenical partners often gives new insights into one’s own tradition. Such a broadening of perspectives can only deepen theological reflection.

Second, study of the Anaphora of Addai and Mari has led to a review of the earlier liturgical tradition in the undivided church. In Christian antiquity, it is clear that before the Middle Ages there was no interest in determining the precise moment of consecration. Rather, reference is often made to the entire eucharistic prayer. Moving beyond the more recent pre-occupation with the precise moment of consecration brings the Catholic Church closer to the Orthodox tradition, as is evident in the 1982 Munich Statement of the Orthodox-Catholic Joint Commission of Theological Dialogue. (Part I, #6) In addition, by shifting the focus away from the moment of consecration, the whole assembly is encouraged to recognize the integrity of the prayer in its entirety and to better experience it as the prayer of the whole community. In light of all the above, perhaps it’s time to celebrate and give more attention to this historic decision.

Sr. Dr. Donna Geernaert, SC, served for 18 years in promoting ecumenical and interfaith relations for the Canadian Conference of Catholic Bishops. She has been a staff member, consultant, and member of numerous multilateral and bilateral theological dialogues in Canada as well as internationally.