Zoroastrian tradition assigns this formula a role unlike any other prayer in the faith: it is held to have been recited by Ahura Mazda before the material creation existed at all, and its recitation is credited in later Zoroastrian literature with having driven back the forces of evil at the very start of the cosmic struggle the tradition describes between Ahura Mazda and Angra Mainyu. That mythological priority is reflected in its ritual weight, it is recited at the start of the Yasna liturgy and repeated a specified number of times within initiation rites including the navjote, the ceremony by which a young Zoroastrian formally takes on the sacred cord and shirt, functioning there as the first substantial prayer a new initiate learns to recite correctly.
As with the other Gathic material in this atlas, the Avestan itself is difficult, and scholarly translations diverge over how to render its central claim, generally understood to assert that as the ahu, the earthly or spiritual lord, is to be chosen, so is the ratu, a term for a spiritual authority or model, to be chosen in accordance with truth, asha, a compressed statement about rightful authority that different translators unpack with considerably different emphasis depending on how they read the technical vocabulary embedded in a very few archaic words. The prayer's practical use as a protective and initiatory formula, recited from memory across the whole community rather than confined to priests, has been far more stable across the centuries than scholarly agreement on its precise grammatical sense.