AH, OM, HUM The novice practitioner inhales a pure white seed syllable OM, and exhales a blue coloured seed syllable HUM. The breath that abides within the body is the red coloured seed syllable AH. The enlightened adept however inhales the Blue coloured seed syllable HUM, and exhales a white syllable OM. The breath that abides within the body remains the red coloured syllable AH. What is happening here? The physical body of the novice practitioner of Mahamudra is still filled with karmic hindrances, and he needs to inhale light and exhale the filthy energy. On the contrary, the enlightened adept seeks to deliver sentient beings, so he inhales the filthy energy of beings and suffers for them. He in turn exhales the breath of light to be absorbed by sentient beings. The Tibetans feel that anyone who breathes in even a little of the breath exhaled by a great yogi of Tantrayana will benefit from it, as the breath of the adept can eliminate karmic hindrances and heal sickness. AH, OM, HUM http://tbc-erooh.org/teachings/books/051_highest_yoga_and_mahamudra/09_circulation_of_mantra_breathing.htm