Dispatching of Usamah ibn Zayd's Army

One of the Prophet's final acts was to organize a military expedition under the command of Usamah ibn Zayd ibn Harithah, the son of his beloved adopted son Zayd who had been martyred at the Battle of Mu'tah. Usamah was only eighteen or twenty years old when appointed commander. Some senior companions questioned the appointment of such a young man, just as they had questioned his father Zayd's leadership at Mu'tah. The Prophet, hearing of this, became angry and addressed it in his final sermon in the mosque: 'If you criticize his leadership, you criticized his father's leadership before him. By Allah, his father was worthy of command, and so is he.' The Prophet personally tied the army's banner and handed it to Usamah. The army was encamped at al-Jurf, just outside Medina, when the Prophet's condition worsened. The expedition was delayed by the Prophet's illness and death, but Abu Bakr, upon assuming the caliphate, insisted on dispatching Usamah's army despite pressure to retain the troops, saying: 'I will not untie a banner that the Messenger of Allah tied.' The army successfully raided the Byzantine frontier and returned safely, and Abu Bakr's resolve became a defining moment of his caliphate.