The Sūtra “The Questions of Dīrghanakha the Wandering Mendicant”

As the Buddha teaches the Dharma to the fourfold saṅgha on Vulture Peak Mountain, the brahmin and wandering mendicant Dīrghanakha approaches and questions the Buddha about his doctrine concerning the incontrovertible relationship between karma and its effects in the world. He then poses a series of ten questions regarding the karmic causes of certain attributes of the Buddha, from his vajra body to the raised uṣṇīṣa on his crown. The Buddha responds to each question with the cause for each attribute, roughly summing up the eight poṣadha vows and the ways he observed them in the past. Dīrghanakha drops his staff and bows to the Buddha, pledging to take refuge in the Three Jewels and maintain the eight poṣadha vows.