In this work, here presented in a complete English edition for the first time, the problem of knowing God is confronted in an original and stimulating way. Taking up the Prophet's teaching that 'Ninety-nine Beautiful Names' are truly predicated of God, the author explores the meaning and resonance of each of these divine names, and reveals the functions they perform both in the cosmos and in the soul of the spiritual adept. Although some of the book is rigorously analytical, the author never fails to attract the reader with his profound mystical and ethical insights, which, conveyed in his sincere and straightforward idiom, have made of this book one of the perennial classics of Muslim thought, popular among Muslims to this day.