Zoroastrianism teaches that the countless spiritual and material worlds are made of the same substance as God. Mazdá Ahûrá creates the infinite worlds from his “own self,” (xweš xwadîh) from his own essence of “mind energy and passionate bright will power,” (See Yasna 34.12, 3rd rhymed verse line and Yasna 39.5, 3rd rhymed verse line.)
The concept that the ahûrás “god beings and god powers” descend from Mazdá Ahûrá and consist of the very stuff from which Mazdá is made of, is of utmost importance for Zoroastrian theology and cosmology.
The gathic ahûrás are the later Avestan Immortals and Yazatás “adorable powers.” Per the sacred Avestan lore, Mazdá Ahûrá is the greatest, brightest and best of all Yazatás or adorable powers.
Yazatá comes from the root yaz/yas. The word literally means “zeal, fervor, intense yearning.” The 2nd word of the poetic gathas is yásá/yáßá “fervent or intense yearning.”
Everything that belongs to Mazdá Ahûrá’s spiritual and material worlds is worthy of “zeal or fervent worship” yaz.
By contrast, anything connected with the agony, narrowness and limitation of mind energy (añgrá mainyü) is unworthy of zeal or fervent worship, (áyesnyæ.)
The material world is therefore good and divine. This per Ugo Bianchi, “pro-cosmic” view of the material creation sets Zoroastrianism markedly apart from many other religions or philosophical systems.
In Zoroastrianism, It is therefore perfectly legitimate to worship any of Ahûrá Mazdá’s spiritual and material creations because ultimately they derive from him and comprise his substance.
One worships Ahûrá Mazdá by fervently worshipping his creations. Because the material world ultimately derives from Ahûrá Mazdá, it is of the utmost importance to keep it pure. Looking after and maintaining the purity of the material creation is the way of worshiping its creator.
Homage paid to the material world was/is one of the most distinctive features of the Mazdá worshiping religion.
Magis or Zoroastrian Priests of the Sassanid Empire demanded of the Zoroastrian apostates who had converted to Christianity, that they should revert to their old faith and prove that they had done so by fervently worshipping the elements specially; “heat of ﬁre, good waters, the victorious sun and the glorious moon.”
Such fervent worship was the ultimate proof of the fervent worship of and intense yearning for Mazdá Ahûrá. But for the Christians such passionate veneration toward nature was to be rejected as pure idolatry. Hence, they first described Zoroastrians as fire worshipers, moon worshipers and sun worshipers.
I like to conclude by the following Avestan hymn of fervent worship to the moon, recited thrice on the nights of full moon.
Courtesy of Didier Calin: Yt 7.3
måηhǝm gaociθrǝm aṣ̌auuanǝm
aṣ̌ahe ratūm yazamaide
tat̰ måηhǝm paiti.vaēnǝm
tat̰ måηhǝm paiti.vīsǝm
raoxṣ̌nǝm måηhǝm aiβi.vaēnǝm
raoxṣ̌nǝm måηhǝm aiβi.vīsǝm