After completing the Fajr Salaah, he sat to teach the students, and spent the entire day teaching them, until it was once again the time for Esha Salaah. Noticing this, I thought to myself, “For a person to have the energy to spend one entire night in ‘ibaadah is possible. Hence, I will observe what happens tonight.”

That night, after all was silent, Imaam Abu Hanifah (rahimahullah) emerged and stood to perform Salaah, and remained engaged in Salaah the entire night, just as he had done the previous night. When the time of Fajr entered, he proceeded to perform the Fajr Salaah, and thereafter spent his day in the same manner as he had spent the previous two days. After Imaam Abu Hanifah (rahimahullah) performed the Esha Slaah, I thought to myself, “For a person to have the energy to spend two entire nights in ‘ibaadah is possible. Hence, I will see what he does tonight (on the third night).”

That night, I observed him doing just as he had done the previous nights (i.e. he spent the entire night in ‘ibaadah), and after the Fajr Salaah, he sat to teach the students as usual. At that moment, I resolved, within my heart, that I would remain with Imaam Abu Hanifah (rahimahullah), until either he passed away or I passed away. I thereafter remained with him in his Musjid until the end of his life.

Mis‘ar bin Kidaam (rahimahullah) has also mentioned, “I never saw Imaam Abu Hanifah (rahimahullah) during the day except that he was fasting, and I never saw him sleep during the night. He would only take a short nap before the Zuhr Salaah.”

Ibn Abi Mu‘aaz (rahimahullah) narrates that Mis‘ar bin Kidaam (rahimahullah) eventually passed away in the Musjid of Imaam Abu Hanifah (rahimahullah), while performing Sajdah.

(Seerat Imaam A’zam Abu Hanifah by Ml Fazl-ur-Rahmaan A’zami pg. 140)