Contact Information


Dr. Bordeianu's research focuses on ecumenical ecclesiologies, especially the dialogue between the Orthodox and Catholic churches, the relationship between the Trinity and the Church, theology of creation, and environmental issues. 

His first book, Dumitru Staniloae: An Ecumenical Ecclesiology has been published by Continuum (2011), also published in Romanian translation, Pr. Dumitru Staniloae: O ecleziologie in dialog (2022). His second book, Icon of the Kingdom of God; An Orthodox Ecclesiology was published by CUA Press in 2023. He is also the editor of, It Is the Spirit Who Gives Life: New Directions in Pneumatology (Washington, DC: CUA Press, 2022). His other works appeared in Pro Ecclesia, Journal of Ecumenical Studies, Downside Review, Journal of Eastern Christian Studies, two Oxford Handbooks, book chapters, etc. He has presented numerous academic papers and was invited guest lecturer nationally and internationally. He has also been interviewed on television, radio, and newspapers.

He also served as President of the Orthodox Theological Society in America (OTSA) and is a member of the North American Orthodox-Catholic Theological Consultation. He is also one of the co-conveners of the Jewish-Christian Dialogue in Pittsburgh, PA. Dr. Bordeianu is involved in various capacities with the most active ecumenical organization in the area, namely Christian Associates of Southwest Pennsylvania.


  • Ph.D., Theology, Marquette University, 2006
  • Th.M., Theology, Duke University, 2000
  • M.A., Theology, Iasi, Romania, 1999


  • The Church - Icon of the Kingdom of God (Ph.D.)
  • Primacies (Ph.D.)
  • Contemporary Ecumenical Ecclesiologies (Ph.D)
  • Ecclesiology (MA)
  • Christology (MA)
  • Theological Foundations (MA)
  • Church of the Early Centuries (MA)
  • Preaching and Catechesis in the Early Church (Independent Study for Aquinas Institute, D.Min.)

Honors College

  • Who Was/Is Jesus?
  • Christology
  • Ecumenism and Anthropology 


  • Eastern Christianity
  • Why Have (A) Faith?
  • Faith and Reason
  • Intro to the Bible
  • Jesus the Christ; Eastern Christianity (advanced undergraduate)
  • Theological Views of the Person

Icon of the Kingdom of God: An Orthodox Ecclesiology (Washington, DC: Catholic University of America Press, 2023).

What is the Church? Some would answer this question by studying the Scriptures, historical sources, and contemporary theologians, thus addressing the theological nature of the Church. Others would answer based on statistics, interviews, and personal observation, thus focusing on the experience of the Church. These theological and experiential perspectives are in tension, or at times even opposed. Whereas the first might speak about the local church as the diocese gathered in the Liturgy presided over by its bishop, the latter would describe the local church as the parish community celebrating the Liturgy together with the parish priest, never experiencing a sole liturgy that gathers an entire diocese around its bishop. Whereas a theologian might describe the Church as a reflection of the Trinity, a regular church-member might experience the Church as a community that manifests the Kingdom of God in its outreach ministries. The present book attempts to bring these two perspectives together, starting from the concrete experience of the Church, engaging this experience with the theological tradition of the Church, extracting ecclesiological principles from this combined approach, and then highlighting concrete situations that reflect those standards or proposing correctives, when necessary. 

Without pretending to be a complete Orthodox ecclesiology, this book addresses, in a dialogical spirit, the most important topics related to the Church. It progresses according to ones experience of the Church from baptism, to the family, parish, Liturgy, and priesthood, followed by analyses of synodality and nationality. 

Arguing that the Church is an icon of the Kingdom of God, this volume brings together the past theological heritage and the present experience of the Church. It pushes the boundaries of classical treatises of Orthodox ecclesiology by being informed and transformed by the practical experience of the Church, the centrality of Jesus’ message of the Kingdom, and by ecumenical encounters

Dumitru Staniloae: An Ecumenical Ecclesiology (T&T Clark, 2011). 

Widely considered the most important Orthodox theologian of the twentieth century, Dumitru Staniloae (1903-1993) contributed significantly to an ecumenical understanding of these themes. Because of his isolation by the Romanian Communist regime, his work still awaits its merited reception, especially given its potential contribution towards Christian unity.  In Staniloae's understanding the Church is a communion in the image of the Trinity. Because there is a continuum of grace between the Trinity and the Church, the same relationships that exist among trinitarian persons are manifested in creation in general, and the Church in particular. In this way, the Trinity fills the world and the Church, determining their mode of existence. Intratrinitarian relationships are manifested in the relationships between humankind and non-human creation, the Church and the world, local and universal aspects of the Church, clergy and the people, and among various charisms. 

“The Reception of Vatican II by the Orthodox Church,” in The Oxford Handbook of Vatican II, edited by Catherine E. Clifford and Massimo Faggioli (Oxford: Oxford University Press, 2023): 493-503. [pdf]

"Orthodox Observers at the Second Vatican Council and Intra-Orthodox Dynamics," in Theological Studies 79, no. 1 (2018): 86-106. [pdf]

"The Unity We Seek: Orthodox Perspectives." In The [Oxford] Handbook of Ecumenical Studies, edited by Geoffrey Wainwright and Paul McPartlan. Oxford: Oxford University Press (Online 2018). [pdf]

"Getting from Conflict to Communion: Ecclesiology at the Center of Recent Lutheran-Orthodox Dialogues and the 2016 Orthodox Council of Crete," in Worship 91, November (2017): 518-539. [pdf]

"The Church: Towards A Common Vision: A Commentary in Light of the Inter-Orthodox Consultation at Agia Napa in Cyprus." In Exchange: Journal of Missiological and Ecumenical Research (Brill) 44, no. 3 (2015): 231-249. [pdf]

"The Biblical Nature of the Church and the Ecclesial Nature of the Bible: An Analysis of Fr. Dumitru Stăniloae's Ecclesiology." In Studii Teologice 2 (2013): 165-­188. [pdf]

"Primacies and Primacy According to John Zizioulas," St. Vladimir's Theological Quarterly 58 (2014): 5-24. [pdf]

Priesthood, Natural, Universal, and Ordained: Dumitru Staniloae's Communion Ecclesiology," Pro Ecclesia 19 (2010): 405-433.[pdf]

"The Contribution of Dumitru Staniloae's Ecclesiology to Ecumenism and Society, Journal of Eastern Christian Studies 62 (2010): 55-85. [pdf]

"Orthodox-Catholic Dialogue: Retrieving Eucharistic Ecclesiology," Journal of Ecumenical Studies 44, no. 2 (2009): 239-65. [pdf]

Review of Dumitru Staniloae, Orthodox Spirituality: A Practical Guide for the Faithful and a Definitive Manual for the Scholar (South Canaan, PA: St. Tikhon's Seminary Press, 2002), in Archaeus 12-13 (2007-2008): 414-416. [pdf] 

"Maximus and Ecology: The Relevance of Maximus the Confessor's Theology of Creation for the Present Ecological Crisis" The Downside Review 127 (2009): 103-126. [pdf]


Dumitru Staniloae: An Ecumenical Ecclesiology, “Ecclesiological Investigations” Series, vol. 13 (London, New York: T&T Clark / Continuum, 2011), ISBN: 978-0-567-33481-7. Paperback edition: T&T Clark / Bloomsbury, 2013, ISBN:978-0-567-31984-5. [Romanian translation] Pr. Dumitru Stăniloae: o ecleziologie in dialog,transl. Adela Lungu (Iași: Doxologia, 2022), ISBN: 978-606-666-873-6.

Icon of the Kingdom of God: An Orthodox Ecclesiology, “Studies in Eastern Christianity”
Series, vol. 1 (Washington, DC: Catholic University of America Press, 2023),ISBN: 978-0-8132-3689-6 (paperback) / 978-0-8132-3690-2 (ebook).

Edited volume and “Introduction”

It Is the Spirit Who Gives Life: New Directions in Pneumatology (Washington, DC:Catholic University of America Press, 2022), ISBN: 978-0-8132-3526-4/7-1