"The merciful Lord reveals to the consciousness of the converting sinner His divine world, in which our spirit is appointed to dwell. Frequently He Himself appears for the purpose of conversion in a visible way, taking on some kind of form and appearing either when a man is awake or in his sleep. In such a way He appeared to the Apostle Paul on his way to Damascus (Acts 9:1-9), to Constantine the Great, to Eustathius Placidas (September 20), to Neanias who was going to torment the Christians (this is the martyr Procopius, July 8), to Patermuthius in his sleep (July 9), and to many others."
- St. Theophan the Recluse, Turning the Heart to God, p.20 (published separately, this is the second part of The Path to Salvation).