But if the following of Islam is understood to mean the obligatory adherence to a certain rite; if being a Mohammedan means conforming to certain restrictions, how can the Sufi be placed in that category, seeing that the Sufi is beyond all limitations of this kind? So far from not accepting the Qur'an, the Sufi recognizes scriptures which others disregard. But the Sufi does not follow any special book. The shining ones, such as Attar, Shams-i-Tabriz, Rumi, Sa'di, and Hafiz, have expressed their free thought with a complete liberty of language. To a Sufi, revelation is the inherent property of every soul. There is an unceasing flow of the divine stream, which has neither beginning nor end.