Zend in the context of "Yasna"

The Avestan alphabet (Avestan: 𐬛𐬍𐬥 𐬛𐬀𐬠𐬌𐬭𐬫𐬵 transliteration: dīn dabiryªh, Middle Persian: transliteration: dyn' dpywryh, transcription: dēn dibīrīh, Persian: دین دبیره, romanized: din dabire) is a writing system developed during Iran's Sasanian era (226–651 CE) to render the Avestan language.

As a side effect of its development, the script was also used for Pazend, a method of writing Middle Persian that was used primarily for Zend commentaries on the texts of the Avesta. In the texts of Zoroastrian tradition, the alphabet is referred to as "the religion's script" (dēn dibīrīh in Middle Persian and din dabireh in New Persian).

Middle Persian literature is the corpus of written works composed in Middle Persian, that is, the Middle Iranian dialect of Persia proper, the region in the south-western corner of the Iranian plateau. Middle Persian was the prestige dialect during the Sasanian era. It is the largest source of Zoroastrian literature.

The Sasanian dynasty (224–654 CE) were natives of that south-western region, and through their political and cultural influence, Middle Persian became a prestige dialect and thus also came to be used by non-Persian Iranians. Following the Arab conquest of the Sasanian Empire in the 7th century, shortly after which Middle Persian began to evolve into New Persian, Middle Persian continued to be used by the Zoroastrian priesthood for religious and secular compositions. These compositions, in the Aramaic-derived Book Pahlavi script, are traditionally known as "Pahlavi literature". The earliest texts in Zoroastrian Middle Persian were probably written down in the late Sasanian era (6th–7th centuries), although they represent the codification of earlier oral tradition. However, most texts, including the Zend commentaries and translations of the Zoroastrian canon, date from the 9th to the 11th century, when Middle Persian had long ceased to be a spoken language, so they reflect the state of affairs in living Middle Persian only indirectly. The surviving manuscripts are usually 14th-century copies.

Pazend (/pəˈzɛnd/) or Pazand (Middle Persian: 𐭯𐭠𐭰𐭭𐭣; Avestan: 𐬞𐬀𐬌𐬙𐬌⸱𐬰𐬀𐬌𐬥𐬙𐬌) is one of the writing systems used for the Middle Persian language. It was based on the Avestan alphabet, a phonetic alphabet originally used to write Avestan, the language of the Avesta, the primary sacred texts of Zoroastrianism.

Pazend's principal use was for writing the commentaries (Zend) on and/or translations of the Avesta. The word "Pazend" ultimately derives from the Avestan words paiti zainti, which can be translated as either "for commentary purposes" or "according to understanding" (phonetically).