“In the eastern part of the Iranian world there arose various schools of Sufism, some of which contain barely disguised Zoroastrian concepts. Figures such as Rumi, Suhrawardi, Mansur al-Hallaj, Nurbakhsh, and even Omar Khayyam all convey essentially Iranian mystical thoughts in Islamic guise, often expressing themselves in their own Persian language rather than Arabic.”

“In the eastern part of the Iranian world there arose various schools of Sufism, some of which contain barely disguised Zoroastrian concepts. Figures such as Rumi, Suhrawardi, Mansur al-Hallaj, Nurbakhsh, and even Omar Khayyam all convey essentially Iranian mystical thoughts in Islamic guise, often expressing themselves in their own Persian language rather than Arabic.”

— Stephen E. Flowers