Sayyiduna Abu Umamah (may Allah be pleased with him) says that I said, "O Messenger of Allah (peace and blessings be upon him), tell me of a deed." He (peace and blessings be upon him) said: "Observe fasting, for there is no deed like it." Imam Abu Bakr (may Allah have mercy on him) says that Muhammad bin Abi Ya'qub is the same narrator about whom Imam Shu'bah (may Allah have mercy on him) said that he is the chief of Banu Tamim.