Brother Yasser Zamora, SA is a Franciscan Friar of the Atonement currently in temporary vows, having made his First Religious Profession in Perú in 2022. A native of Nicaragua who also holds Peruvian nationality, Brother Yasser earned his bachelor’s degree in philosophy from the Catholic University of Nicaragua. His theological studies were completed in Perú at the ISET Juan XXIII Institute, which operates in convention with the Pontificia Università Urbaniana of Rome. He earned his master’s degree in Psychopedagogy from the Latina University of Costa Rica. He is currently based with the Franciscan Friars of the Atonement community in Assisi, Italy, where he is pursuing his Licentiate in Franciscan Spirituality at the Theological Institute of Assisi.
But we ought always to thank God for you, brothers and sisters loved by the Lord, because God chose you as firstfruits to be saved through the sanctifying work of the Spirit and through belief in the truth. He called you to this through our gospel, that you might share in the glory of our Lord Jesus Christ.
2 Thessalonians 2:13-14
To stand in Thessaloniki, a city layered with the history of the early Church and the modern challenges of a divided world, felt like stepping directly into the Apostle Paul’s salutation. The recent ecumenical gathering of the Ecclesiological Investigations International Research Network was not merely a series of academic sessions; it was, for me, a profound personal experience of the biblical call to shared glory and sanctifying truth. Gathered were sisters and brothers “loved by the Lord” from countless nations and Christian denominations, yet all were called by the same Gospel. This meeting, focused on the unfinished legacy of the Council of Nicaea in 325, 1700 years ago this year, was a three-day immersion in the practical and spiritual necessity of Christian unity.
The deepest personal insight during this gathering came from realizing that Christian unity is not about becoming a seamless, institutional bureaucracy, but about embracing the organic diversity with which God has already graced us.
The Beauty of Difference in Communion
The deepest personal insight during this gathering came from realizing that Christian unity is not about becoming a seamless, institutional bureaucracy, but about embracing the organic diversity with which God has already graced us. Walking from “table to table,” speaking with people whose theological vocabulary or liturgical practices differed (sometimes profoundly) from mine, I experienced firsthand what it means to be a “body . . . knit together by every ligament” (Ephesians 4:16).
There is a common, understandable fear in modern society that unity equals uniformity, oppression, or the dominance of the powerful. If unity were merely a political or structural consolidation, this fear would be justified. But our experience in Greece enacted a deeper truth: that true Christian unity is a union of love, mutual dependence, and reciprocal enrichment. It is not a denial of difference, but a communion based on difference. As one voice reflected, our faith is fundamentally about “bringing together what has been broken.” The visible body of the Church – expressed in our traditions, worship, and doctrine – must be nothing less than the “visible expression of this original Christian Spirit.” The Spirit is the single force that unifies the whole, not a central human hierarchy within its own ideological borders. Not only were we able to gather from diverse Christian churches, cultures, and countries, but we were also able to move beyond those more difficult invisible frontiers: ideology, the prevailing culture of individualism, and so on. Having overcome all of that, the Holy Spirit is the one who decentralizes and moves hearts toward unity.
The historical process of [the Creed’s] formulation – fraught with political pressure and theological debate – reminded us that the Church’s journey toward truth is one of ongoing discernment, driven by the desire to safeguard the core narrative of God’s saving act.
The Creed as a Living Horizon
The academic investigations continually returned to the Nicene-Constantinopolitan Creed. It was explored not as a static, ancient document, but as a dynamic statementand a “horizon”for our unity today. The historical process of its formulation – fraught with political pressure and theological debate – reminded us that the Church’s journey toward truth is one of ongoing discernment, driven by the desire to safeguard the core narrative of God’s saving act.
The key takeaway was both simple and profound: The Creed articulates those essential few things “on which the significance of faith depends.” By agreeing on these things – that God is one, that Jesus Christ is begotten of the Father and not created, and that the Spirit gives life – we are set free to express the vast diversity of culture and expression in all other matters. This is an ecumenical language rooted not in compromise, but in the integrity of the Trinitarian God, revealed through the kenōsis, the self-emptying love, of Christ.
The Enduring Charism of At-One-Ment
The ecumenical movement, as a spirituality, has a modern tradition as deep as its ancient theological roots. Our shared time in Thessaloniki was a powerful confirmation that unity is not a bureaucratic achievement but a charism – a spiritual gift – that continues to be lived out personally and collectively within the Church. I think here of Fr. Paul Wattson of Graymoor and Mother Lurana White, who, in 1898, co-founded the Franciscan Friars and Sisters of the Atonement. They championed the vision of “At-One-Ment” – the healing of fragmentation in the self, the church, and the world – as the core of their religious life and mission. Their enduring legacy includes establishing the Church Unity Octave (now globally recognized as the Week of Prayer for Christian Unity), demonstrating that the pursuit of unity is not just a theological project, but a concrete, personal, and perennial call to prayer proposed by the Church itself. Their work shows that before dialogue becomes official, it must be embraced as a profound, Christ-centered way of life.
To gather in Thessaloniki for this ecumenical meeting was to experience the biblical vision of “At-One-Ment” made tangible. It was an intellectual and incarnate journey through the history of the Nicene Creed, but, more profoundly, it was a spiritual encounter with the unbroken whole of the Body of Christ.
The Necessity of Collective Resistance
Finally, the meeting was a stark reminder that ecumenism is not a luxury for theologians; it is an absolute “necessity” and an “act of collective resistance against all the sin of humanity.” Sitting in Thessaloniki, many questions emerged, but at a crossroads with global migration, an especially urgent question hung in the air: What concrete actions can we take to move from dialogue to tangible collaboration on issues like environmental protection and aid for refugees? And concerning this, we all shared many insights and prayers.
To gather in Thessaloniki for this ecumenical meeting was to experience the biblical vision of “At-One-Ment” made tangible. It was an intellectual and incarnate journey through the history of the Nicene Creed, but, more profoundly, it was a spiritual encounter with the unbroken whole of the Body of Christ. I recall the warmth of shared coffee breaks, the prayers, and the intensity of theological debate, seeing men and women from the Orthodox, Catholic, Anglican, and other denominations – from every corner of the world – united by the singular purpose of answering Christ’s prayer for unity. As we talked, prayed, and reflected, the city of Paul itself seemed to whisper a powerful message: Our differences are not obstacles; they are the Spirit’s gifts, enriching the common truth we share.
This personal reflection ends where the biblical text begins: in gratitude, and in action rooted in the Spirit’s work. I am so grateful for the Ecclesiological Investigations Network, and I hope that it continues gathering people around the world, as we look forward together to new ways to build a better, peaceful, and unifying world. Our shared faith, confirmed in the foundational Creeds and lived out in the organic diversity of the Body of Christ, gives us the spiritual resource to face these global problems together. The challenge now for all of us – those in religious life, the clergy, the scholars, and every member of the Body – is to ensure that our unity in the Spirit becomes ever more visible as a beacon of love with justice and hope in a broken world. We are chosen not for isolated identity, but to share in Christ’s glory through a life of unified witness.
This article originally appeared in Ecumenical Trends 55.2 (March/April 2026), a publication of Graymoor Ecumenical & Interreligious Institute. The journal offers distinctive perspectives where the church, the academy, and the interfaith field coincide, and combines reporting on current developments in ecumenical/interreligious affairs with accessible scholarship, interviews, and pastoral reflection on the dynamics of religious difference on common ground. Find out more, and subscribe to Ecumenical Trends (print and/or online), by clicking here.