" To attain the reality of unity, the believer must undergo deeper and deeper self-forgetting in the remembrance of God. There is no god but God now comes to mean, "there is no existing thing but God." Someone asked Sa'd ad-din Hamuya, "What is God?" He answered, "That which exists is God." The questioner asked, "What is the world?" He answered, "Nothing exists but God." (p. 225) "

― , Mingled Waters: Sufism and the Mystical Unity of Religions