See, I want to impart to you true knowledge of prelest, so that you should guard against it, and not cause great harm to yourself and ruin your soul through ignorance. For the human self-will is easily inclined to the enemies' side, especially in the case of the inexperienced, since these are more assidiously pursued by them. All around, near to beginners and the self-willed, the demons are wont to spread the nets of thoughts and pernicious fantasies and prepare moats for their downfall, since their city is still in the hands of the barbarians ... If you ...see something either sensory or spiritual, within or without, be it even the image of Christ or of an angel or some saint, or if an imaginary light pervades your mind, in no way accept it. The mind has in itself a natural power of dreaming and can easily build fantastic images of what it desires in those who do not apprehensively pay attention, and so cause themselves harm. Memories , too, of good and bad things will often sudden imprint their images in the mind, and thus entice it to dreaming. (ie) which is spiritual delusion <prelest>. ~ St. Gregory of Sinai
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