The person who embodied the revival of Avestic studies between 1950 and 1989 was Karl Hoffmann (1915-1996). The synthesis of his work was published in 1989 with Der Sasanidische Archetypus, written with Johanna Narten. But how did we get here?
Between 1889 and 1896,Geldner edited the Avesta, which he divided into 5 books: Yasna ("sacrifice"), Yašts ("sacrifices"), Vīdēvdād ("ritual arrangements to keep demons at bay"), the Visperad, which exists only as a complement to the Yasna, and the Xorda Avesta, an anthology of extracts from either the Yasna or the Yašts. The history of the Avesta, according to him, is in three stages: 1. the original Avesta, containing the Gāθās and the great Yašts, had been written and archived, but was burnt by Alexander; 2. the Sassanid Avesta is made up of preserved parts of the original Avesta and new compositions, which was also written and archived; 3. the Avesta "Books of the Parsis", handed down to us by manuscripts, attests to the haphazard remains of the great Sassanid Avesta. With the discoveries made in Central Asia at the beginning of the 20th century, we realize that it is difficult to imagine a text written before a certain period.
The Andreas theory
Carl Friedrich Andreas also sees three phases: 1. the Urtext is the original text; 2. the Arsakidischer Text is the first written version, notated in a consonant script; 3. the Vulgata is the vocalized text, albeit often incorrectly. Andreas' hypothesis was to enjoy considerable success.
The triple refutation
This was the work of three independent scholars. Georg Morgenstierne and Walter Bruno Henning set out to show that there is no false vocalization in the Avesta text, but simply phonetic developments specific to Avestic. As for Harold Walter Bailey, his focus is not on the linguistic aspect, but rather on the historical. By analyzing the testimony of the Dēnkard, he draws up a new history of the transmission of the Avesta: 1. oral transmission phase; 2. the Avesta was first published during the reign of Xosrō I; 3. the text we have is a second edition, based on the fragments that were saved from this first edition.