date of compilation or rewriting of Avesta; From claims to reality!

One of the ambiguous points of Zoroastrian history is the date of compilation or rewriting of Avesta. Many possibilities and theories have been proposed in this regard; Some consider the original Avesta as a written document presented by Zoroaster, which was destroyed by Alexander the Great and was rewritten in later periods. Others consider this source as an oral document and claim that it was compiled by Zoroastrian priests in later periods. There are also possibilities regarding the date of compilation or rewriting of this document; Some consider it to be the Parthian Balash era and others to the Sassanid Ardeshir era. This chaotic situation in the history of the compilation of Avesta and the uncertainty as well as the existence of some historical clues and evidences have led to the entry of other hypotheses in this regard, which cannot be ignored. One of these hypotheses; Compilation of this document in the post-Islamic era, especially during the Abbasid Caliphate, coincides with the strengthening of religious branches and schools. In this article, we have tried to prove with different proofs and evidences, especially by using the signs from Islamic texts, especially the Imamiyyah tradition, that Zoroastrians did not have any documents with a divine color such as the Avesta book before the Islamic conquests.