Fire altar

A fire temple in Zoroastrianism is the place of worship for Zoroastrians, often called dar-e mehr (Persian) or agiyari (Gujarati). In the Zoroastrian religion, fire (see Atar), together with clean water (see Aban), are agents of ritual purity. Clean, white "ash for the purification ceremonies [is] regarded as the basis of ritual life", which "are essentially the rites proper to the tending of a domestic fire, for the temple [fire] is that of the hearth fire raised to a new solemnity".

For, one "who sacrifices unto fire with fuel in his hand ..., is given happiness".

As of 2017^[update], there were 50 fire temples in Mumbai, 100 in the rest of India, and 27 in the rest of the world.

First evident in the 9th century BCE, the Zoroastrian rituals of fire are contemporary with that of Zoroastrianism itself. It appears at approximately the same time as the shrine cult and is roughly contemporaneous with the introduction of Atar as a divinity. There is no allusion to a temple of fire in the Avesta proper, nor is there any Old Persian language word for one.

That the rituals of fire was a doctrinal modification and absent from early Zoroastrianism is also evident in the later Atash Nyash. In the oldest passages of that liturgy, it is the hearth fire that speaks to "all those for whom it cooks the evening and morning meal", which Boyce observes is not consistent with sanctified fire. The temple is an even later development: from Herodotus it is known that in the mid-5th century BCE the Zoroastrians worshipped to the open sky, ascending mounds to light their fires (The Histories, i.131). Strabo confirms this, noting that in the 6th century, the sanctuary at Zela in Cappadocia was an artificial mound, walled in, but open to the sky, although there is no evidence whatsoever that the Zela-sanctuary was Zoroastrian (Geographica XI.8.4.512). Notice that, although the "burning of fire" was a key element in Zoroastrian worship, the burning of "eternal" fire, as well as the presence of "light" in worship, was also a key element in many other religions.

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