The Rev. Dr. John Chryssavgis is an author and theologian who serves as advisor to the Ecumenical Patriarch on environmental issues. He is a clergyman of the Greek Orthodox Archdiocese of America. In January 2012, he became the first in history to receive the title of Archdeacon of the Ecumenical Throne by His All-Holiness Ecumenical Patriarch Bartholomew.
Rev. John Chryssavgis was born in Australia on April 1, 1958. He matriculated from the Scots College in Sydney, New South Wales in 1975 and received his degree in Theology from the University of Athens in 1980. He received a diploma in Byzantine Music from the Greek Conservatory of Music in 1979 and was awarded a research scholarship to St. Vladimir's Theological Seminary in 1982. He completed his doctoral studies in Patristics at the University of Oxford in 1983. Chryssavgis read patristic theology at Oxford. His work and writing have focused on medieval theology, as well as on the history of the Eastern Church. He holds degrees in theology and sacred music. His teaching has covered wide-ranging topics, such as theological, political, and social developments, themes and personalities of the Middle Ages, including cultural and religious relations and tensions between East and West. His interests have embraced the areas of spirituality, ecology, and liturgy. His research has specialized in the ascetic thought and practice of the early Church, especially from the desert tradition of Egypt (fourth century) through the regions of Palestine (fifth-sixth centuries) and Sinai (seventh century). After several months in silent retreat on Mt Athos, he worked with the Greek Orthodox Primate in Australia (1984-94) and was co-founder of St Andrew's Theological College in Sydney, where he was Sub-Dean and taught Patristics and Church History (1986-95). He was also Lecturer in the Divinity School (1986-90) and the School of Studies in Religion (1990-95) at the University of Sydney.Template:Verify credibility
In 1995, he moved to Boston, where he was appointed Professor of Theology at Holy Cross School of Theology and directed the Religious Studies Program at Hellenic College until 2002. He established the Environment Office at the same School in 2001. He has also taught as professor of Patristics at Balamand University in Lebanon.
In recent years, he has published several books and countless articles in international journals and encyclopedias in the area of religion and ecology, social justice and peace, with forthcoming books including John Climacus: from the Egyptian Desert to the Sinaite Mountain (Ashgate, UK, Winter 2004); and Light Through Darkness: Insights into Orthodox Spirituality (Orbis Books, Summer 2004)
He currently serves as theological advisor to the Ecumenical Patriarch on environmental issues.
He lives in Maine.
- "About Rev. Dr. John Chryssavgis" 
- Persons and Events: Historical Moments in the Development of Orthodox Christianity, Archdiocese of Australia, Sydney, 1985. [Out of print]
- Fire and Light: Aspects of the Eastern Orthodox Tradition, Light and Life Publications, Minneapolis MN, 1987.
- Ascent to Heaven: The Theology of the Human Person, Holy Cross Press, Boston MA, 1989. [Out of print]
- The World My Church (with Sophie Chryssavgis), David Lovell Publishing, Melbourne, 1990. Reprinted with changes by Holy Cross Press, Boston MA, 1998. Five printings to date.
- The Desert is Alive: Dimensions of Australian Spirituality, Joint Board of Christian Education, Melbourne, 1990. Second Printing 1993.
- Repentance and Confession, Holy Cross Press, Boston MA, 1990. Second Printing 1996. Third printing 1998.
- Love, Sexuality, and Marriage, Holy Cross Press, Boston MA, 1996. Second printing 1998.
- The Way of the Fathers: Exploring the Mind of the Church Fathers, Analecta Vlatadon, Thessalonika, 1998. [Out of print]
- Beyond the Shattered Image: Insights into an Orthodox Ecological World View, Light and Life Books, Minneapolis MN, 1999.
- Soul Mending: The Art of Spiritual Direction, Holy Cross Press, Boston MA, 2000. Second printing 2002.
- In the Footsteps of Christ: the ascetic teaching of Abba Isaiah of Scetis, SLG Press, Oxford UK, 2001. [With P.R.Penkett]
- The Body of Christ: A Place of Welcome for People with Disabilities, Light and Life, Minneapolis MN, 2002.
- Abba Isaiah of Scetis: The Ascetic Discourses, Cistercian Publications, Kalamazoo MI, 2002. [With P.R.Penkett]
- In the Heart of the Desert: The Spirituality of the Desert Fathers and Mothers, World Wisdom Books, Bloomington IN, 2003. 2nd revised edition 2008. Also translated into Italian: Bose Publications, Italy 2004.
- Cosmic Grace, Humble Prayer: Ecological Vision of Ecumenical Patriarch Bartholomew, Eerdmans Books, Grand Rapids MI, 2003. Revised and updated, 2009.
- Letters from the Desert: A Selection of the Spiritual Correspondence of Barsanuphius and John, St. Vladimir's Seminary Press, New York NY, 2003.
- The Way of Tears: A Spirituality of Imperfection, In Greek: Akritas Publications, Athens, 2003.
- The Way of the Fathers: Exploring the Mind of the Church Fathers, Light and Life Books, Minneapolis MN, 2003
- Light through Darkness: Insights into Orthodox Spirituality, Orbis Press: Maryknoll; and Darton Longman and Todd: London, 2004
- John Climacus: from the Egyptian desert to the Sinaite mountain, Ashgate, London, 2004.
- The Reflections of Abba Zosimas: Monk of the Palestinian Desert, SLG Press: Oxford, 2004. Reprinted 2006.
- The Ecumenical Patriarchate: a historical guide, Ecumenical Patriarchate Publications, Constantinople, 2005. 2nd revised edition, 2007.
- The Correspondence of Barsanuphius and John, with translation, introduction, notes and complete indices (scriptural, patristic, subject and names). For Catholic University Press, Washington DC, 2 volumes, 2006 and 2007.
- In the World, Yet Not of the World: Social and Global Initiatives of Ecumenical Patriarch Bartholomew, Fordham University Press, New York, 2009.
- Speaking the Truth in Love: Theological and Spiritual Exhortations of Ecumenical Patriarch Bartholomew, Fordham University Press, New York, 2010.
- In the Footsteps of St. Paul: An Academic Symposium, Holy Cross Press, Boston MA, 2011. [With Archbishop Demetrios Trakatellis of America]
- On Earth as in Heaven: Ecological Vision and Initiatives of Ecumenical Patriarch Bartholomew, Fordham University Press, New York, 2012.
- Remembering and Reclaiming Diakonia: The Diaconate Yesterday and Today (Brookline, MA: Holy Cross Orthodox Press, 2009)