Abu Hamza al-Thumali was pious and righteous companion of Ali Zayn al-Abidin. He was also a companion of Muhammad al-Baqir and Ja'far al-Sadiq. Al-Najashi said: “He was the best of our companions and the most reliable of them in narration and tradition.” It was reported on the authority of Ali al-Ridha who said: “Abu Hamza at his time is like Salman at his time.” His supplication was accepted. His sons died martyrs with the great revolutionist, Zayd ibn Ali. Abu Hamza al-Thumali has related that during the month of Ramadhan, Ali Zayn al-Abidin used to spend a greater part of the night in prayers and when it used to be the time of beginning of the fast he recited a supplication which later known as Du'a Abi Hamzah al-Thumali (The supplication of Abi Hamzah al-Thumali). This supplication has been recorded in the book Misbah al-Mutahijjid of Shaykh Tusi.