Zoroaster prophecy that saw a return of Sassanid emperor Bahram: Shoghi Effendi also stated that Zoroaster lived roughly 1000 years before Jesus. The Greeks—in the Hellenistic sense of the term—had an understanding of Zoroaster as expressed by Plutarch, Diogenes Laertius, and Agathias that saw him, at the core, to be the "prophet and founder of the religion of the Iranian peoples," Beck notes that "the rest was mostly fantasy". Zoroaster was set in the ancient past, six to seven millennia before the Common Era, and was described as a king of Bactria or a Babylonian (or teacher of Babylonians), and with
Zoroaster 1500 and 500 BCE. Some scholars such as Mary Boyce (who dated Zoroaster to somewhere between 1700–1000 BCE) used linguistic and socio-cultural evidence to place Zoroaster between 1500 and 1000 BCE (or 1200 and 900 BCE). The basis of this theory is primarily proposed on linguistic similarities between the Old Avestan language of the Zoroastrian Gathas and the Sanskrit of the Rigveda (c. 1700–1100 BCE), a collection of early Vedic hymns. Both texts are considered to have a common archaic Indo-Iranian origin. The Gathas portray an ancient Stone-Bronze Age bipartite society of warrior-herdsmen and priests (compared to Bronze tripartite society;