Zoroastrianism

Zoroastrianism is one of the most ancient religions about which anything is known, and is over 3,000 years old₁. It still has followers today_2,3. It arose in ancient pre-Islamic Iran "in the eastern and south-central regions of the Iranian world, between the great mountain ranges of the Hindu Kush and Seistan, an area that today is divided between Iran and Afghanistan" and it still survives there, although it faces constant and sometimes violent persecution. It was supposedly founded by Zarathustra (Zoroaster)₁.

It is in many ways monotheistic, in that there is a single creator god (Ahura Mazda)₄, and this makes it a significant precursor to many of the religions that later rose in a similar vein, including the monotheistic religions Judaism, Christianity and Islam. But Zoroastrianism is often called dualistic₅ because most concerns are to do with Ahura Mazda's twin children "Spentu Mainyu ('beneficient spirit') and Angra Mainyu ('hostile spirit')"₁. The hostile spirit is better known by its Middle Persian equivalent: Ahriman. Their different temperaments arise "from the choice they made between 'truth,' asha, and the 'lie,' druj, between good thoughts, good words, and good deeds and evil thoughts, evil words and evil deeds"₁. The battle between these two define the theology of Zoroastrianism and this dualistic idea of 'spiritual warfare' remain with monotheistic religions to this day, especially Christianity and Islam₅, although the perceived balanced between God and Satan is different.

“Zoroastrian scholarship has always had to contend with considerable difficulties because sources of knowledge about the religion, in particular those pertaining to its earliest period, are few and conflicting. The Avesta, a collection of texts gathered in writing during the fourth and sixth century CE, has survived only in part, and it presents a heterogeneous picture.”

"The Encyclopedia of Religion" by Eliade Mircea (1987)₆

Problematic Doctrine: Incest and Decline: Zoroastrianism, like Judaism, has strict rules against marrying outsiders (called exogamy)₇. Followers of Zoroaster in India are called Parsis, and some of that community moved to Hong Kong, but at even their height there were never more than 100 of them₇. Such a small community, only marrying each other and the occasional Parsi from Mumbai in India, struggled to expand₈. Incest is part of official Zoroastrian doctrine, wherein it is called Xvaetvadatha - marriage between cousins in particular was called 'marriages made in heaven'. Zoroastrian culture is also very wary of accepting conversions₇, and this combined with incest and a shrinking base of adherents has placed Zoroastrianism in a poor position globally, and the religion is "significantly declining"₇.

Mithraism: The Roman mystery religion Mithraism developed out of Zoroastrian ideas. See: Mithraism and Early Christianity.