Was Buddhism taught from a single sacred book?

No, Buddhism was not taught from a single sacred book. Instead, its teachings are found in a variety of texts, including the Tripitaka (Pali Canon), Mahayana Sutras, and various other scriptures that differ across traditions. These texts encompass a wide range of teachings, philosophies, and practices attributed to the Buddha and his followers. Thus, Buddhism is characterized by a diverse set of scriptures rather than a singular sacred book.