Text: Q-1. What light should be used [for healing]? A-1. "Any penetrating light. That of the dry heat, or that that acts the quickest with the blood stream, see? for, as is seen, this is the effect of light - of whatever nature that may be applied to a body: All bacilli or all germs are afraid, as it were, of light - or light is destructive to all. Some, as is seen, accumulate in heat that is not penetrating. Hence the variations in the quartz light, the ultraviolet light, the blue light, the red light - each one taking out that that filters through the system. Hence for this, that one most penetrating without being destructive to the tissue proper." Cayce (140-21)

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