I still somewhat believe in Zoroastrianism-although I can't exactly be sure that there is One God called Ahura Mazda & one Anti God called Ahriman who will have a cosmic battle & that we can choose sides in this etc-it sounds somewhat far fetched to me, but I like the values that Zarathushtra propagated, in his writings I see great universally applicable wishdom, although the latter additions by Persians again have some unpleasant stuff.
If I restrict myself to only Zarathushtra's writings- I see an astonishingly morally relevant text, unlike the OT, Quran or writings by Jesus' Apostles, Zarathushtra's writings are very morally correct & I don't think they'd appear immoral even today.
I think religion is something so integral to humans that it can't completely disappear(at least it hasn't yet) & if one religion fades away, a newer one replaces it so its best to have a good religion as a bulwark against another not so great one!
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That is why I'd like Iran to be Zoroastrian again, or perhaps Bahai or even Christian-Islamic reformer Reza Aslan's parents had left Iran after the Islamic Revolution & migrated to U.S.A., his mom converted to Christianity, dad remained irreligious & virulently anti Islam-Reza surprised & disappointed his parents by reverting to Islam,perhaps if he'd been given other viable options like Zoroastrianism & the Bahai faith, which are also rooted to his country & culture, he would've chosen one of these & propagated these.
If Iranian or Islamic youth quit Islam someday, I fear atheism might be too much of a blank space to endure for long & there'd be a huge God shaped hole in their lives-that could be filled by alternative faiths more tied to their country & cultures.
Of course, faiths can't exactly be tailor made for individuals to suit all their tastes & in case of millennia old faiths there're bound to be some stuff that are unpleasant & in faiths which millions follow there're bound to be people who do violent or grotesque stuff, but there should be enough good in the faiths tenets & practices & it should be able to adapt reasonably to modernity.
The problem with Islam IMO is that the supposed
good stuffin the faith-ie it being free from racial discrimination are simply fanciful propaganda. Or that Sufi Islam, born to a great deal due to contact with other non Islamic faiths seems to crumble so easily as soon as there's increasing contact with Arabia & decreasing numbers of non Islamic minorities.
Sufi Islam owed a great deal to non Islamic faiths like Zoroastrianism, Buddhism & so on-it did flourish in Iran & Afghanistan(eg Rumi) as long as there were still unconverted non Islamic minorities & a not wholly Islamized culture-it crumbled & was replaced by stonings, floggings & death penalty for apostasy as soon as Islam became all powerful.