“The worth and meaning of every ascetic practice are to be estimated in terms of quietude, lucidity of spirit, love, and purity of heart. Anything that does not lead to these is worthless, for instead of liberating us from self-preoccupation, it only reinforces our illusory and obsessive concern with our own ego and its victory over the ‘not-I.’ True quietude and purity of heart are impossible where this division of the ‘I’ (considered as right and good) and the ‘not-I’ (considered as threatening) governs our conduct and our decisions.”

Merton, Thomas. “The Spiritual Father in the Desert Tradition.” (1968) in Selected Essays. Edited with an introduction by Patrick F. O’Connell. Maryknoll, NY: Orbis Books, 2013, p. 320