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btw i got that information on the time it occurs from this book;The Dreamers Dictionary, by Stearn Robinson & Tom Corbett,i however didn't read most of the book,has anyone read it all?(i managed only to get this bit from a preview of the book on the internet..).plus @nunya yeah i think it can happen at any time of day e.g Abraham of the bible in genesis 15:12 he had his dream of the covenant with God in the evening..