Shaikh ‘Abd al-Qadir al-Jilani is arguably the greatest figure in the history of Sufism. His teachings have attracted millions to Islam and helped countless Muslims understand the spiritual journey that this great religion represents. The current work consists of fifteen short letters in which the Shaikh describes spiritual experiences and knowledge that are attained through striving against one’s base desires and committed devotion to Allah. They are written in a highly mystical language, using a peculiar style whereby each sentence or group of sentences is followed by a related Qur’anic text. In effect, the letters represent a Sufi experiential interpretation of the quoted Qur’anic verses. While small in size, this exceptionally charming and poetically beautiful work is immensely profound. This translation of the book is based on three manuscripts. The translator, who has previously co-translated into English Shaikh ‘Abd al-Qadir’s Purification of the Mind (Jila’ Al-Khatir), has also added a commentary.