Zoroastrians believe that as soon as the breath has left the body, it becomes impure. Death is considered to be the work of Angra Mainyu, the embodiment of all that is evil, whereas the earth and all that is beautiful is considered to be the pure work of God. Contaminating the elements (Earth, Air, Fire and Water) with decaying matter such as a corpse is considered sacrilege.

Instead of burying the corpse, Zoroastrians traditionally laid it out on a purpose built tower (dokhma or ‘Tower of Silence’) to be exposed to the sun and eaten by birds of prey such as vultures.