During [every] day and night, Ibn ‘Ataa would [only] sleep for two hours.
Every day, my father would read a seventh [of the Qur.aan], and he would take a very light sleep after ‘Ishaa. He would then [awake and] stand [the night] in prayer and supplicate until the morning.
I have not eaten my fill for 16 years, except on one occasion; and [on that occasion] I placed my hand in my mouth and induced myself to vomit.
Abu Haneefah used to be called a stake [of wood], because of the abundance of his [standing in] prayer.