Middle Persian strata and the survival of Zoroastrian vocabulary in Shāhnāme

Differences in style and poetic or narrative techniques lead to the conclusion that the Middle Persian text is not Ferdowsi's source, but that the majority of figures of speech (metaphors, hyperboles, parataxis) and other characteristics of the epic style are already well developed there, and that we are faced with a single narrative melted into two different molds: that of holy war and the glorification of the martyr who died for his faith in the AZ version, and the heroic and epic gesture for the ShN.

Among the most significant differences are the motivations for going to war: in AZ, the Turanian Arjāsp is indignant at the conversion of Goshtāsp and his court to the religion of Zoroaster, whereas in the ShN it is Zoroaster himself who sets things alight. In AZ, Goshtāsp wants to avoid his brother's death at all costs, until the visionary Jāmāsp predicts the happy outcome of the battle with Isfandyār who captures Arjāsp - a passage absent from the more detailed ShN. The ShN also omits the arrow incantation (the formula pronounced by Goshtāsp for the arrow destined to kill Zarēr's assassin), the appearance of Zarēr's soul who warns his son against a poisoned arrow, and finally the intervention of Zarēr's horse (cf. his Avestic epithet aspāiiaoδa - "who fights on horseback") who saves Bastūr from certain death. Some of these discrepancies can be explained by the fact that specific references to Zoroastrian beliefs such as the fate of the soul (Zarēr becomes a revenant because he was unable to benefit properly from funeral rites) no longer had a place in Daqiqi's epic, not to mention the performative role of sacred formulas. Moreover, Bastūr is either replaced by Isfandyār in the ShN or accompanied by him.

We can conclude that not only does the ShN not deliberately erase Zoroastrian elements, but the narrative generally retains its full Zoroastrian essence. The ancient religion is not presented as an exotic or artificial element: the terminology is chosen, understood and perfectly assumed. We could go so far as to say that Ferdowsi's message is perhaps more "Zoroastrian" than that of the Middle Persian text. Whereas the latter is presented as a tragedy intended to be sung and staged in a dramatic performance where the innocent martyr is celebrated, the Persian version lays the groundwork for the creation of the character who embodies the ideal warrior, namely Isfandiyār, uniting courage and faith and entrusted with the primordial role of spreading the new religion. In short, Zoroastrianism ceases to be a mere plot element and becomes here the main narrative scheme, the common thread, that accompanies the invincible Isfandiyār towards his destiny: to die fighting his Sistani alter ego, Rostam.