Quick questions on Xerxes' religious policy and the daiva inscription: HSC Ancient History

The single most important source for this dot point is the daiva inscription, catalogued as XPh, copies of which were found at Persepolis in the three official languages of the empire: Old Persian, Elamite and Babylonian. After the usual praise of Ahura Mazda and a list of the lands Xerxes ruled, the inscription includes a famous passage in which the king declares that, in a place where the daivas (false gods) had formerly been worshipped, he, by the favour of Ahura Mazda, destroyed their sanctuary and proclaimed that "the daivas shall not be worshipped," worshipping Ahura Mazda reverently in their place.

The most dramatic charge against Xerxes is that, after two Babylonian revolts in 484 BC (led by Bel-shimanni and Shamash-eriba), he sacked the great temple of Marduk (Esagila) and carried off, or melted down, the golden cult statue of the god Bel-Marduk. This story comes from Herodotus (Histories 1.183) and later classical writers (Ctesias, Arrian, Strabo), and it long underpinned the image of Xerxes the temple-destroyer.

Achaemenid religion under Xerxes centred on Ahura Mazda and on fire. The clearest archaeological evidence is the royal tomb reliefs at Naqsh-e Rustam, which show the king standing on a raised platform before a fire altar, beneath a winged symbol (variously interpreted as Ahura Mazda himself or as the royal khvarnah, the divine glory of kingship, this identification is itself debated). Herodotus (Histories 1.131-132), writing as an outside Greek observer, reports that the Persians had no cult statues or roofed temples in the Greek sense, that they sacrificed to the sky and the elements in open, high places, and that a priestly class, the magi, presided over the rites and chanted a "theogony."