Three neighs of the horse
Three neighs of the horse (Tib. རྟ་མགྲིན་གྱི་རྟ་སྐད་ཐེངས་གསུམ་, tamdrin gyi také teng sum, Wyl. rta mgrin gyi rta skad thengs gsum) is the mandala practice associated with Hayagriva or Lotus Speech. From Hayagriva's point of view the universe is gullible and the horse's neigh is to awaken and provoke gullible beings.
The three neighs are waking the world to the fact that samsara and nirvana are non-originated, offering the whole world and demanding obedience.
Further Reading
- Chögyam Trungpa, The Tantric Path of Indestructible Wakefulness (volume 3) (Shambhala, 2013)