Idries Shah on Hafiz

Khaja Shamsuddin Hafiz (literally Master Sun of Faith, the Protector, he who knows the Koran by heart)died in 1389.One of the greatest of all Persian poets, his works are known as the Interpreter of the Secrets and the Speech of the Invisible. His collection, the Diwan, conceals, in seemingly sensual verse, many Sufi experiences. It is used as a textbook, and also (by the vulgar) for omens, by opening it at random. Originating in Isfahan, the family migrated to Shiraz. The date of his death is concealed in a poem which appears on his tomb, which itself gives the clue to the fact that it is concealed in the numerical cipher used by the Sufis: "If thou wouldst know when he sought a place in the dust of Musalla, seek the date in the dust of Musalla." "Dust of Musalla" (khak-i-musalla) decodes to the number 791, the equivalent in the Moslem calendar for the year 1389. Hafiz was the teacher of kings and at the same time beloved of the people. His influence is still second to none in Persian literature.

Taken from The Sufis, by Idries Shah.p.425-426