Abu Nasr Seraaj Toosi
Sheikh Abu Nasr Seraaj, one of the great theosophists in the 10 th century. He was an Iranian perfect scholar and researcher and was familiar with most of the sciences of his own time. Abu Nasr Seraaj was the first person who wrote books on Sufism. He has a famous book on Sufism called: "Brightness in Sufism", in this book besides subjects on Sufism, there are also other subjects such as: relations between Sufism and Islam. Abu Nasr died in 988.
Sources :
Translation of farhangsara.com
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