The Airyaman Ishya lives in two moments of Zoroastrian life, marriage and healing, and in one moment beyond history. At weddings the prayer is recited over the couple, a usage that follows naturally from Airyaman's character as the divinity of friendship, concord and right relationship, so that the community's oldest surviving benediction still opens its marriages. In healing, the tradition remembers Airyaman as the one who cures.
The twenty second chapter of the Vendidad tells how the evil spirit created diseases by the myriad, and how the healing of them was entrusted to Airyaman, whose prayer accordingly carries therapeutic power, recited for the sick alongside practical medicine rather than in place of it. The prayer's furthest horizon is eschatological.
In the Pahlavi tradition of later Zoroastrian literature, the Airyaman Ishya is the prayer whose recitation accompanies the frashokereti, the final renovation of the world, when evil is undone and the living and the risen dead are made whole, the last healing of which every recited cure is a rehearsal. That span, from a wedding canopy to the end of the world, explains the prayer's rank among the four great mantras of the faith, and why Zoroastrian priests still teach it to children in the same dialect in which it was first composed some three thousand years ago.