Yashts

The Yashts are a set of twenty one hymns, each addressed to a single yazata, a being worthy of veneration in the Zoroastrian system, and together they are the most narratively vivid part of the Avesta. Where the Yasna is defined by ritual function and the Vendidad by legal procedure, the Yashts read as praise poetry with embedded myth: they describe the deeds, appearance and power of their subject, and several preserve stories found nowhere else in the surviving Avesta.

The best known examples include the Mihr Yasht, addressed to Mithra as a guardian of covenants and oaths, the Aban Yasht, addressed to the waters and to the goddess Anahita, and the Bahram Yasht, addressed to Verethragna, a being associated with victory. Because each Yasht was composed and transmitted somewhat independently before being gathered into a single collection, they vary considerably in length, poetic quality and apparent age, and a few are thought to preserve pre-Zoroastrian material that was reworked to fit the tradition's theology rather than composed fresh within it.

Individual Yashts remain in active devotional use, recited on the calendar day associated with their yazata, which keeps them closer to living practice than some of the Avesta's more purely liturgical material.

All the Yashts as they survive are in Younger Avestan, but that shared surface language conceals considerable variation in underlying age. Specialists studying meter, vocabulary and mythic content have argued that several Yashts, the Mihr Yasht and Aban Yasht prominent among them, carry material that predates the systematic form Zoroastrianism took under the Achaemenid and Sasanian empires, reshaped and given a Zoroastrian theological frame without fully erasing the older layer beneath it.

That unevenness makes the Yashts a frequent point of comparison for scholars studying the relationship between Zoroastrianism and the wider Indo-Iranian religious world it emerged from, since figures such as Mithra and Anahita have close counterparts and cognates elsewhere in Iranian and Indian tradition. The Yashts were transmitted orally for a very long period before being fixed in the Avestan alphabet devised under the Sasanians, and like the rest of the Avesta they were later accompanied by a Pahlavi Zand for priests who no longer read Avestan as a living language.

The Farvardin Yasht, honoring the Fravashis, the guardian spirits of the dead, is recited during the Zoroastrian new year period and remains among the most widely used of the collection in contemporary practice, which shows how individual Yashts keep a devotional life distinct from the set as a whole.