Books
- Bradley, Ian. Following the Celtic Way: A New Assessment of Celtic Christianity
- Newell, John Phillip.
- Anam Cara, A Book of Celtic Wisdom
- Christ of the Celts: The Healing of Creation
- Sacred Earth, Sacred Soul: Celtic Wisdom
- O’Loughlin, Thomas. Celtic Theology – Humanity, World and God in Early Irish Writings
- Stanz, Julianne. Braving the Thin Places – Celtic Wisdom to Create a Space for Grace
- Stewart, R.J.. Celtic Gods, Celtic Goddesses
Compilations
- Heroes of the Dawn, Celtic Myth, Time Life Books, edited by Peter Bentley
- Carmina Gadelica: Hymns and Incantations, (9th ed.) compiled by Alexander Carmichael
- Celtic Christianity Spirituality – Annotated Writings Explained, annotated by Mary C. Earle, foreword by John Phillip Newell
- Tielhard de Chardin – A Book of Hours, edited by Kathleen Deignan, CND and Libby Osgood, CND
Note: These works were referenced or studied in various formation series between 2022-2025.