Harith al-Muhasibi

Al-Muhasibi (781–857) was the founder of the Baghdad School of Islamic philosophy, and a teacher of the Sufi masters Junayd al-Baghdadi and Sari al-Saqti.

His full name is Abu Abdullah Harith bin Asad al-Basri. He was born in Basra in 781. Muhasibi means self-inspection/audit. It was his characteristic property. He was a founder of Sufi doctrine, and influenced many subsequent theologians, such as al-Ghazali.

He wrote many books about theology and Tasawwuf (Sufism), among them Kitab al-Khalwa and Kitab al-Ri`aya li-huquq Allah ("Obeying God's Permits").

In al-Khalwa, in a discourse on fear and hope:

Al-Khalwa's argument elsewhere cites al-Hasan al-Basri. The above pericope was later transplanted into a fictional response by al-Hasan to 'Umar b. 'Abd al-Aziz.

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