Kenneth Johnson observes that these are the standard colours of Western alchemy, and that if the hand follows the body positions in the usual alchemical sequence - black, white, yellow and red - the result is the action of crossing oneself.  One wonders then whether there may not be some Knights Templar or other esoteric Christian influence here, although Johnson points out that this is not an exclusively Christian gesture.

I might add that these colours also correspond in part to the three subtle states of consciousness (shunyas or "empties") in Tibetan Buddhism: i.e.: "the mind of white appearnace", "the mind of red near-attainment", and "the mind of black near-attainment"; this last being followed by the Clear Light or direct experience of Reality.
 

 It would seem that Semnani's latifa have a double meaning: they refer both to psychic centres (=chakras) and to a succession of subtle bodies (Sanskrit kosha, Greek okhema) or levels of self.  It is interesting that some modern clairvoyant and theosophical writers, who are totally ignorant of this particular Sufi teaching, also match up the seven chakras with seven bodies or levels of self (e.g. according to Barbara Brennan the base or Muladhara chakra corresponds to the etheric body, the second or Swadhishthana chakra to the emotional body, and so on), and also to colours (usually a rainbow sequence from red through to violet).  Even though the two sets of correspondences are quite distinct, the principle of their equivalence is nevertheless quite similiar.
 
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