Sufis' knowledge of God is not based on what anyone has told them, but rather comes through personal experience of traversing the inner realms that connect each human being with his or her Source. This volume explores the 'Spiritual Faculties' (translated as understanding, remembering, intuition, insight, imagination, etc.) by which we 'sense' inner realities, the 'Spiritual Organs' which embody the subtler aspects of a human being (soul, spirit, intellect, etc.), and finally, the nature and types of spiritual knowledge, described in the classical writings of the great sufis.
Nafs is the term that sufis apply to the faculty that engenders self-centeredness, attachment to the passions, and anger and aggressiveness in a person.
How can one attain Your lane,
when all one sees
Are deserts all around Your lane
because of one's nafs?-Sana'i