Zoroastrianism

Zoroastrianism is the religion and philosophy based on the teachings ascribed to the prophet Zoroaster (Zarathustra, Zartosht). Mazdaism is the religion that acknowledges the divine authority of Ahura Mazda, proclaimed by Zoroaster to be the one uncreated Creator of all (God). Mazdaism is also widely known under its ancient Iranian name Mazdayasna, meaning "the worship of wisdom".

As demonstrated by Zoroastrian creed and articles of faith, the two terms are effectively synonymous. In a declaration of the creed — the Fravarānē — the adherent states: "…I profess myself a devotee of Mazda, a follower of Zarathustra." (Yasna 12.2, 12.8)

Some scholars have suggested that Zoroastrianism was where the first prophet of a monotheistic faith arose, claiming Zoroastrianism as being "the oldest of the revealed credal religions, which has probably had more influence on mankind directly or indirectly, more than any other faith". It is sometimes argued that Zoroastrianism had an influence on later Judaism, and therefore has also indirectly influenced Christianity.

Zoroastrianism was once the dominant religion of much of Greater Iran. As of 2007 the faith has dwindled to small numbers; some sources suggest that it is practiced by fewer than 200,000 worldwide, with its largest centers in India and Iran. For details, see adherents below.