The veneration of fire was an established practice of the Mazdayasnis much before the time of prophet Zarathushtra. Fire had been venerated not only as a symbol of the divine, but also having a divinity of its own.
King Hoshang of the Peshdadian dynasty started the reverence to fire, centuries before the advent of prophet Zarathushtra. While hunting, King Hoshang accidentally came across the brilliance of fire when he tried to kill a huge snake. Regarding this Firdausi says, “Nushad mār Koshtah valiken zarāz, azān tab-e-sang ātash āmad farāz “The snake did not die, but from the latent energy of the stone fire came out.” He asked the Mazdayasnis to make a Kebla (centre of worship) of fire and pray before it.
In the Shahnameh, Firdausi says, ke urā kurughī chunin hadayah dād, hamīn ātesh ān gāh kebleh nehād, be goftā kurughīst in izadi, parastī be āyad agar bekhardi. “God bestowed on Hoshang the gift of light, and he immediately made a Keblā of that fire. He said, “this is the nur (light) of God, he who is wise shall venerate (parastesh) it.” This fire was then established as Adar Khurdad. It was the first fire to be established in a place of worship. Then King Hoshang celebrated Jashane Sadeh to commemorate the discovery of divinity in fire.
King Jamshed established Adar Farnbagh on Mount Khorehmand. He specially created a section of society called Athravans (priests tending fire) to look after it. This fire prevented Zohak from taking charge of the Khoreh (divine energy) of Jamshed. Kayanian king Kae Khushru established the special fire Adar Gushnasp on Mout Asnavant.
Prophet Zarathushtra himself was a fire-priest (āthravan) and used to pray before fire. Later as one of the proofs of his being a prophet, Zarathushtra gifted the special fire Adar Burzin Meher to king Kae Gushtasp. About this fire, Firdausi says Ke bi khāko ābesh bar āvarde ham, negeh kun bud ātash chun kardeh ham; Ke ān meherburzin bi dud bud, munavvar ne az hizmo az ud dud. “This fire was made without physical elements or water, this fire – Adar Burzin Meher is without fumes, it does not require fuel or incense.” Later Kae Gushtasp established the Adar Burzin Meher on Mount Raevant.
When prophet Zarathushtra established the Mazdayasni Zarthosti religion, he accepted fire as the living emblem of Ahura Mazda. He extended the understanding of the concept of fire to embrace the idea of physical and spiritual energies. In Zoroastrian religion, Asha Vahishta, that is, Ardibahesht Ameshaspand, became the guardian of fires and energies.