Humbach Helmut. The Gāthās of Zarathushtra and the other Old Avestan texts. Vol. 1

In collaboration with Josef Elfenbein and Prods O. Skjærvø. — Heidelberg: Winter, 1991. — Vol. 1: Introduction, Text and Translation. — (Indogermanische Bibliothek. Erste Reihe, Lehr- und Handbücher). — ISBN: 9783533044734.Zarathushtra was the founder and prophet of the pre-Islamic religion of Iran which covered not only present-day Iran and Afghanistan, but also large parts of the adjacent territories in former Soviet Union and Pakistan, and probably had an extensive influence throughout the entire Achaemenian Empire. Comparison with the Rigveda, the earliest document of Indic literature, shows that Zarathushtra in his religious teaching developed and reformed many the religious ideas inherited from the Proto-Indo-Iranian period; other inherited ideas he rejected completely, replacing them by new concepts. The only authentic religious and literary heritage left to posterity by Zarathushtra are his five Gathas, a collection of seventeen religious hymns. These form the nucleus of the Yasna, the great Mazdayasnian liturgy, which constitutes about one third of what has come down to us of the original Avesta (chapters 28-34, 43-51, and 53, of the Yasna).