The Avesta () is the primary collection of religious literature of Zoroastrianism from at least the late Sassanid period (ca. 6th century CE). It is composed in the Avestan language, with the oldest surviving fragment of a text in the Avestan language dating to 1323 CE. The Avesta texts fall into several different categories, arranged either by dialect, or by usage. The principal text in the liturgical group is the Yasna, which takes its name from the Yasna ceremony, Zoroastrianism's primary act of worship, at which the Yasna text is recited.
https://en.wikipedia.org/wiki/Avesta
The Avesta () is the primary collection of religious literature of Zoroastrianism from at least the late Sassanid period (ca. 6th century CE). It is composed in the Avestan language, with the oldest surviving fragment of a text in the Avestan language dating to 1323 CE. The Avesta texts fall into several different categories, arranged either by dialect, or by usage. The principal text in the liturgical group is the Yasna, which takes its name from the Yasna ceremony, Zoroastrianism's primary act of worship, at which the Yasna text is recited.
