Avesta: The Sacred Books of the Parsis is a comprehensive translation of the holy scriptures of Zoroastrianism, one of the world's oldest religions. Karl F. Geldner's work captures the spiritual, philosophical, and liturgical aspects of the Zoroastrian faith, offering insight into the beliefs, prayers, hymns, and rituals that have shaped this ancient tradition. The Avesta provides a window into the teachings of Zoroaster, emphasizing the duality between good and evil, the importance of moral choice, and the reverence for the divine in everyday life. This sacred text is central to understanding the culture and spiritual practices of the Parsis, whose historical influence extends from ancient Persia to the modern world. Geldner’s meticulous translation helps preserve the Avesta’s intricate language and meaning, serving as an important resource for both scholars and those seeking to explore Zoroastrianism.