Atar
Atar (Avestan ātar) is the Zoroastrian concept of holy fire, sometimes described in abstract terms as "burning and unburning fire" or "visible and invisible fire" (Mirza, 1987:389).
In the Avestan language, ātar is an attribute of sources of heat and light, of which the nominative singular form is ātarš, source of Persian ātaš (fire). It was once thought to be etymologically related to the Avestan āθrauuan / aθaurun (Vedic atharvan), a type of priest, but that is now considered unlikely (Boyce, 2002:16). The ultimate etymology of ātar, previously unknown (Boyce, 2002:1), is now believed to be from the Indo-European *hxehxtr- 'fire'. This would make it related to the Latin (black) and possibly a cognate of the Slavic (fire).
In later Zoroastrianism, ātar (in middle Persian: ādar or ādur) is iconographically conflated with fire itself, which in middle Persian is ātaxsh, one of the primary objects of Zoroastrian symbolism.
Atar is already evident in the Gathas, the oldest texts of the compendium of the Avesta and believed to have been composed by Zoroaster himself. At this juncture, as in the Yasna Haptanghaiti (the seven-chapter Yasna that structurally interrupts the Gathas and is linguistically as old as the Gathas themselves), atar is still—with only one exception—an abstract concept simply an instrument, a medium, of the Creator and is not yet the divinity (yazata) of heat and light that atar was to become in the later texts.
In the most ancient texts, atar is a medium, a faculty, through which judgement is passed and reflects the pre-Zoroastrian institution of ordeal by heat (Avestan: garmo-varah, heat ordeal; cf. Boyce 1996:ch. 6). So, for example, justice is administered through atar (Yasna 31.3, 34.4, 36.2, 47.2), the blazing atar (31.19, 51.9), through the heat of atar (43.4), through the blazing, shining, molten metal (ayangha Khshushta, 30.7, 32.7, 51.9). An individual who has passed the fiery test, has attained physical and spiritual strength, wisdom, truth and love with serenity (30.7). However, among all the references to atar in the oldest texts, it is only once addressed independently of Ahura Mazda. In this exception, atar is spoken of in the third person masculine singular: "He detects sinners by hand-grasping" (Yasna 34.4). Altogether, "there are said to have been some 30 kinds of fiery tests in all." (Boyce, 2002:1)
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