“These Iranian poems, known as Gathas or ‘songs’, are still recited in the Old Avestan language in which they were memorized orally for centuries, until they were committed to writing in a specially-invented alphabet around the sixth or seventh century CE. Our earliest extant Avestan manuscripts date from the thirteenth century CE. The transmission of the Gathas from Ahura Mazda to humanity is attributed to an Iranian precursor named Zarathushtra. This view is expressed formally at an early stage in the corpus of Avestan texts in references to ‘the Gathas of Zarathushtra’ (Y 57.8). The Gathas, two prayers (known as Yatha ahu vairyo or Ahuna Vairya, and Airyema Ishyo), and a short Old Avestan liturgy, are the primary and oldest sources for our understanding of ‘Zoroastrianism’ in its earliest form. The Sitz im Leben of these texts, and their linguistic comparison with the Sanskrit of the Rig Veda, suggests a similar date of around midsecond millennium BCE. There are, however, widely variant opinions concerning this dating, and no consensus likely unless new data is found.”¹

“Zoroastrians regard the Gathas as the authoritative, original teachings of Zarathushtra. For some, anything that is perceived as differing from Gathic teaching is not considered to be authentically ‘Zoroastrian’, although may be recognized as part of a general continuum. The question as to what extent later, non-Gathic materials reflect either a continuity or divergence of belief and practice was raised in the mid-nineteenth century, but still resonates with Zoroastrians and non-Zoroastrian scholars today, some of whom maintain that anything extraneous to the Gathas must be defined as ‘post-Gathic Zoroastrianism’ or ‘post-Gathic Mazdaism’.”²