The difficulty is that much of the materials generally...

The difficulty is that much of the materials generally considered being very old are much later or at least they “function” in a much later theological organism. The branch of the Aryans who in about the eleventh century B. C.

detached themselves from their brethren, penetrating afterwards into the jungles of India (a natural place for magic and richest mytho‑poetical phantasy) and made the yellow and dry plateau of Iran their country, had obviously brought with them their naturalistic religion, clearly delineated in the Vedas and rather similar to that of old Rome and Greece. The sacrifices of animals (e. g., the ox) and the ceremonial libation of the fermented juice of a plant, haoma (Skr.

soma), were frequent and taken as sacred rites. At a certain moment, not yet determined with sufficient clearness, though the majority of scholars seem now to fix it at the sixth century B.C., the remarkable personality of a religious reformer, Zarathustra, appeared in the oriental zone of the Iranian plateau. His name still resists all attempts at etymological interpretation. “The man with the old camels” seems to be the most accepted one.

Zarathustra, possibly utilizing a pre‑existing naturalistic sky‑god (Varuna), created a new monotheism, so strong that the name of the old gods (devas) came to signify “demons.” This was, up to some time ago, a “classical” theory of the historians of Mazdaism, but now it seems to cede to new hypotheses maintaining that the demonization of the devas was prior to Zarathustra.

Henning even asserted that Zarathustra's reform was a “protest against monotheism.” The seventeen hymns (Gathas), written in a rather archaic language and forming the central part of the Avesta are generally considered to be the work of Zarathustra himself. The Gathas uphold veneration for a single supreme God, Ahura Mazdah, the “Wise Lord” (according to some like Pagliaro, “the Thinking Lord”).

He is accompanied by a cortege of abstract quasi‑personified powers or attributes, the six Amesha Spentas (Holy Immortals): Asha (the Cosmic Law or Righteousness), Vohu Manah (Good Thought or Benevolence), Khshathra (Sovereignty), Armaiti (Piety, Docility), Haurvatat (Integrity), Ameretat (Immortality).

The Gathas reject rites and sacrifices, especially the ritual killing of cattle and the Haoma cult, preach a very high personal ethic, and enforce wise social laws, foremost of which is the fostering of agriculture against nomadism.