This book serves as a comprehensive guide into the ancient faith of Zoroastrianism, one of the world's oldest continuously practiced religions. It explores the religion's core tenets, its rich history from ancient empires to a persecuted minority, and its modern challenges. Central to the faith are the teachings of the prophet Zarathustra and the revolutionary monotheistic revelation of Ahura Mazda as the supreme God. The book explains Zoroastrianism's profound dualistic theology of the cosmic battle between good (Asha) and evil (Druj), emphasizing personal ethics summarized as Good Thoughts, Good Words, and Good Deeds. It also covers its sacred rituals, divine hierarchy, sacred texts, and rites of passage. Despite being a small global community, Zoroastrianism's historical and intellectual impact is immense, shaping foundational concepts of later major religions and maintaining an enduring commitment to its spiritual light and purity.