Avesta: the legend of Hystaspes

The Denkard, a summary of the partly lost Great Avesta of the sixth century, contains the story Zarathustra and his protector Hystaspes. Denkard 7.4.65-87 is offered here in the translation by Mary Boyce.

Zarathustra and Hystaspes

[] Zarathustra departed alone, at the counsel and command of Ahuramazda, to the court of Hystaspes and the ordeal of that terrible contest [between him and his opponents]. [...] 

[] Hystaspes, through his great wisd