Greg Hillis

Gregory K. Hillis

Professor in the Practice of Theology; Executive Director of the Aquinas Center of Theology


PhD, McMaster University, 2008
MA, McMaster University, 2003
BA (Hons), University of Waterloo, 2001


(404) 712-0031


Dr. Greg Hillis joined the Aquinas Center as its executive director in 2023. Prior to taking this position, he was Professor of Theology and Religious Studies at Bellarmine University in Louisville, Kentucky for 15 years. He completed his doctoral research on early Christian theology, with a particular focus on the Trinitarian theology of Cyril of Alexandria. He has published a number of academic articles on Cyril’s theology and ecclesiology, and wrote the introduction to a significant translation of Cyril’s Glaphyra published by Catholic University of America press.

More recently, he has turned his attention to the life, theology, and spirituality of the American Trappist monk, Thomas Merton. His 2021 book on Thomas Merton, Man of Dialogue: Thomas Merton’s Catholic Vision (Liturgical Press) was awarded the “Louie” award from the International Thomas Merton Society for best new book on Merton, as well as a first-place award in the category of “Biography” by the Catholic Media Association. In addition to academic articles published in Studia PatristicaCistercian Studies Quarterly, and The Merton Annual, Hillis writes for public theology for a broader audience, publishing essays regularly in America and Commonweal.


Man of Dialogue: Thomas Merton’s Catholic VisionCollegeville, MN: Liturgical Press, 2021


“A Selective Hermeneutic,” America, June 2023, 53-54.

“In Praise of the Pitch Clock,” Commonweal, May 17, 2023

“The case against confirming baptized Christians at the Easter Vigil,” America, April 3, 2022

“Take me out to the ballgame: The majesty (and agony) of playoff baseball,” America, November 2, 2022

“Thomas Merton can still teach us a lot about nuclear war,” America, April 8, 2022

“Unity Without Reduction,” Commonweal, February 10, 2022

“Remembering Thich Nhat Hanh, the Buddhist monk who Thomas Merton called a brother,” America, January 24, 2022

“I love Pope Francis’ commitment to dialogue—which is why his Latin Mass restrictions confuse me,” America, December 22, 2021

“’The Mystical Fire of Christ’s Charity’: Thomas Merton, the Eucharist, and the Meaning of Dialogue,” Cistercian Studies Quarterly , 55.1 (2020): 77-95.

“Thomas Merton in Love,” The Tablet, December 12, 2020, 8-9.

“We’re All Monks Now,” America, May 25, 2020, 36-39.

“What the coronavirus tells us about the Trinity—and ourselves,” America, March 19, 2020

“Introduction,” St Cyril of Alexandria, Glaphyra on the Pentateuch – Volume 1: Genesis Washington: Catholic University of America Press, 2019

“Introduction,” St Cyril of Alexandria, Glaphyra on the Pentateuch – Volume 1: Genesis Washington: Catholic University of America Press, 2019

“Letters to a Black Catholic Priest: Thomas Merton, Fr. August Thompson, and the Civil Rights Movement,” The Merton Annual 32, 2019, 114-136.

“A convert’s journey with St. John Henry Newman,” America October 16, 2019

“A Sign of Contradiction: Remembering Fr. August Thompson,” Commonweal October 2019, 29-31

“Thomas Merton, the problem of war and the character of Christian nonviolence,” Australian Broadcasting Corporation, Religion and Ethics, January 29, 2019

“Model of the Church,” Amercia May 13, 2019, 44-45

“‘We are Both Christ’: Learning from Merton the Correspondent How to be a Friend,” What I am Living For: Seven Lessons from the Life and Writings of Thomas Merton, Ava Maria Press, South Bend, IN , 2018

“Louie” Award for Best New Book on Thomas Merton, International Thomas Merton Society, 2023

“First Place” in the category of “Biography,” awarded for Man of Dialogue: Thomas Merton’s Catholic Vision by the Catholic Media Association, 2021

In the media

October 5, 2023

Remembering Thomas Merton—and his book that changed my life

August 19, 2023

What the Catholic Church can learn about change from baseball’s pitch-clock innovation

May 22, 2022

Universal Love in Christianity and Buddhism

May 12, 2020

Living like monks in quarantine

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