When there is evidence of being obsessed by a spirit-entity, the only radical cure is exorcism. Unless one has the guidance of an adept, the following is suggested: First, he should try sleeping with a green-coloured night light burning throughout the night. It should be placed not more than eighteen inches from the bed. If this fails, then an ordinary non-coloured electric bulb may be substituted, thus giving a stronger light. The inconvenience of trying to sleep with the bedroom illuminated will only exist for a few days or a few weeks and will vanish as the eyes become accustomed to the new habit. It may even be averted by covering the eyes with a black silk bandage. In addition to this, he must pray, and combine this with creative meditation, wherein he actually pictures the freed condition desired during the night. He should also pray and meditate prior to retiring.
-- Notebooks Category 11: The Negatives > Chapter 4 : In Thoughts, Feelings, Violent Passions > # 131
