Spiritual hunger is a living, radiant fire put by God into hearts so that the ego can be burned; when it has been burned, this fire becomes the fire of longing, which never dies, either in this world or the next. There is no quicker way to God than spiritual hunger; if it travels through solid rock, water gushes forth. Spiritual hunger is essential for the Sufis; it is the showering of God's mercy on them.
~ by Abu Said Ibn Abi Khayr