Catholic Saints Podcast — St. Gregory of Nyssa

Augustine Institute | Host: Mary McGeehan | Guest: Dr. Chris Mooney
Episode Date: January 10, 2026

Overview

This episode of the Catholic Saints podcast, hosted by Mary McGeehan with guest Dr. Chris Mooney, shines a spotlight on St. Gregory of Nyssa — one of the three great Cappadocian Fathers of the 4th century. The discussion delves into his unique background, theological contributions (especially on the Trinity and infinity of God), profound influence as a spiritual writer and preacher, and his revolutionary stance on issues such as slavery and the dignity of all people. The episode explores how Gregory’s life and writings can inspire contemporary Catholics and pastors.

Key Discussion Points & Insights

1. Who Was St. Gregory of Nyssa? (00:27–02:53)

• Geographical and Historical Setting
  • Nyssa was located in what is now modern-day Turkey. Gregory was known as the bishop of Nyssa and part of the Cappadocian Fathers, alongside his brother Basil of Caesarea and friend Gregory of Nazianzus.
  • “The saints come in clusters…they all lived in the 4th century during this great period of flourishing in early Christian theology.” — Dr. Chris Mooney (01:36)
• Societal and Church Context
  • The beginning of the 4th century marked the end of severe Christian persecutions, with Christianity becoming accepted and then the official religion of the Roman Empire.
  • Gregory was born around 335 AD and died in 395 AD, living through and shaping theological developments post-Nicaea.

2. Family, Education, and Personal Background (03:04–05:20)

• Big, Holy Family
  • Gregory was raised in a family of 10 children, several of whom are saints. His sister, Macrina, was particularly influential as both educator and spiritual role model.
  • “Gregory himself was actually a homeschooler…taught at home by his older sister, Macrina.” — Dr. Chris Mooney (03:42)
• Personal Life
  • Likely married, but his wife passed away young; Gregory embraced a monastic way of life thereafter.

3. Unique Contributions and Social Stances (05:21–08:43)

• Pioneering Abolitionist
  • Remarkably, Gregory stands out as speaking unequivocally against slavery—one of the first figures in history to do so, based on his Christian understanding of Christ as the image of all humanity.
  • “Gregory…is really the first witness we have in the long Christian tradition of proclaiming that slavery was an offense against God.” — Dr. Chris Mooney (05:51)
• Champion for Christ-like Holiness
  • Chose to write the life of his sister Macrina, highlighting sanctity and Christ-likeness above fame, wealth, or conventional achievement.

4. Gregory as Theologian — Major Teachings (08:43–12:16)

• Defender of the Trinity
  • Gregory was pivotal in defending the doctrine of the Trinity against Arianism and in shaping the text of the Nicene Creed.
  • He addressed the philosophical concept of God's infinity: Ancient thinkers saw infinity as a flaw, but Gregory articulated the idea that “God is infinite” in goodness, love, and joy.
  • “God is an ocean, an infinite, endless ocean of joy. And Gregory in his theology, although it can be hard to work through…helps us to see this.” — Dr. Chris Mooney (10:36)

5. Gregory as Preacher and Spiritual Writer (12:16–17:35)

• Pastoral Relevance

  • Gregory’s surviving works include homilies on the Lord’s Prayer and the Beatitudes, which demonstrate his pastoral heart.
  • Example from his homilies:
    • “For the effect of prayer is union with God. And if someone is with God, he is separated from the enemy. Through prayer we guard our chastity, control our temper, and rid ourselves of vanity…” — Gregory of Nyssa, quoted by Dr. Mooney (13:34)
  • Prayer, for Gregory, is “intimacy with God and contemplation of the invisible. It satisfies our yearnings and makes us equal to angels.” (14:14)

• On the Lord’s Prayer

  • Explains why we pray “Hallowed be Thy name”: Not because God changes, but because we want God’s holiness manifest in us.
  • “No good can come to us without God’s help…The most important for me is that God’s name should be glorified through my life.” — Gregory of Nyssa, paraphrased by Dr. Mooney (16:25)

6. Pastoral Challenges and Heresies Faced (18:14–22:25)

• Challenges of the Era
  • Despite being a golden age of theology, Gregory’s era was plagued by heresies—especially Arianism, which denied Jesus’ divinity and the doctrine of the Trinity.
  • Clarification of complex doctrine was necessary. Gregory’s classic treatise, “To Ablabius: On Not Three Gods,” addressed misunderstandings about the Trinity.
  • “Part of what Gregory does is respond to this, but he also knows the doctrine of the Trinity is hard to understand.” — Dr. Chris Mooney (21:33)

7. How We Know About the Great Councils (22:40–24:01)

• Historical Records
  • Councils like Nicaea and Constantinople kept ‘acta’ (deeds, proceedings), often with lists of attendees; supplemented by letters and later histories.

8. Gregory’s Continued Relevance and Inspirations (24:01–25:55)

• Why Look to Gregory Today?
  • Dr. Mooney encourages listeners and pastors to immerse themselves in Gregory’s homilies, emphasizing two key takeaways:
    • Contemplation of Christ should impact how we relate to others and society.
    • Gregory “plumbed the depths” with challenging topics—Trinity, prayer, and God’s infinity—but rendered them approachable and relevant to Christian life.
  • “Gregory’s presenting to us what it really means to believe in an infinite God who is infinitely satisfying, is crucial to the whole, to our whole way of thinking as Christians.” — Dr. Chris Mooney (25:48)

Notable Quotes & Memorable Moments

• On the Value of Holiness:
  “She [Macrina] stood out because she was holy and because she was configured to Christ. And Gregory saw that.” — Dr. Chris Mooney (08:22)

• Prayer as Intimacy:
  “Prayer is intimacy with God and contemplation of the invisible. It satisfies our yearnings and makes us equal to angels.” — Gregory of Nyssa [quoted] (14:14)

• Revolutionary Social Teaching:
  “Gregory…is really the first witness we have in the long Christian tradition of proclaiming that slavery was an offense against God.” — Dr. Chris Mooney (05:51)

• On God’s Infinity:
  “God is an ocean, an infinite, endless ocean of joy.” — Dr. Chris Mooney (10:36)

• On ‘Hallowed be Thy Name’:
  “No good can come to us without God’s help…The most important for me is that God’s name should be glorified through my life.” — Dr. Chris Mooney paraphrasing Gregory (16:25)

• On Living as a Christian:
  “Believing in Christ, believing who Christ is, seeing him as he really is, has to make a difference in how we relate to the world.” — Dr. Chris Mooney (24:41)

Timestamps for Important Segments

• 00:27–02:53: Introduction to St. Gregory, historical context, Cappadocia
• 03:04–05:20: Gregory’s family, education, and spiritual upbringing
• 05:21–08:43: Gregory’s abolitionism and view of Christian dignity
• 08:43–12:16: Theological contributions—Trinity and God’s infinity
• 12:16–17:35: Homilies on prayer and the Lord’s Prayer
• 18:14–22:25: Pastoral challenges, heresies, and the Councils
• 22:40–24:01: Historical documentation of Councils
• 24:01–25:55: Application for today and Dr. Mooney’s recommendations

Takeaways for Listeners

• Read Gregory’s Homilies: Especially those on the Lord’s Prayer for spiritual enrichment and practical guidance.
• Model Holiness: As Gregory did, by viewing Christ at the center and letting that affect how we treat others.
• Deepen Your Theological Understanding: Value the intellectual heritage Gregory offers, particularly concerning the Trinity and the infinite love of God.
• Seek Gregory’s Intercession: Especially for pastors, theologians, families (large or homeschooling), and anyone wrestling with the relationship between faith and social issues.

“Gregory’s understanding of…what it really means to believe in an infinite God who is infinitely satisfying, is crucial to our whole way of thinking as Christians.” — Dr. Chris Mooney (25:48)