Zoroastrians low key believe Allah is the malevolent force of evil Angra Manyu, who exists in opposition to Ahura Mazda the creator God. Zoroastrians believe that the creator came upon the dominion of darkness in which Angra Manyu dwelled and willed creation into it and drove it back. But Angra Manyu ever seeks to reclaim what was stolen from it. The fire lighting ritual, and the ritual of tending to the fires is done to create constant light and creation even in the face of destruction and primordial entropy. The sacred fires are kept constantly lit, and the priests are constantly growing trees to be turned into wood that are then used to feed the fire, which in theory so long as the faithful continue to nurture new growth to be turned into firewood and stoke the flame, means that a given fire could be lit continuously for thousands of years and across generations of people.
Its a rather fascinating philosophy, and you can see how it influenced later religions like Judaism and Christianity. The christian concept of being "A light", or God as "The Light of the World" is cribbed directly from Zoroastrianism. As a Christian myself, I can say that its far closer to my own understanding of God then what the Muslims believe, even if theologically they are off the mark. I wouldn't mind attending a fire festival to ward off Satan. But I would mind being told to turn off my brain and become a slave which is what they do at Mosques.
