The Expedition of Usama ibn Zayd RA

Toward the end of Safar in the 11th year of the Hijrah, a few weeks before his death, the Prophet ﷺ ordered an expedition to the lands of the Romans (the Byzantine Empire), aiming at al-Sham and in particular Palestine. He called on the sahaba, including Abu Bakr RA, Umar RA, and many of the senior Companions, to gather their arms, and appointed Usama ibn Zayd RA (then only 17 or 18 years old, and the son of his freed slave and adopted son Zayd ibn Harithah RA, who had been killed by the Romans at Mu'tah) to lead them. Some in Madinah murmured that Usama was too young and not of Quraysh to lead senior sahaba, though none of the senior Companions themselves objected; the Prophet ﷺ rebuked the criticism, reminding the people that Zayd ibn Harithah RA's own leadership had once been doubted the same way, and declared Usama the most beloved of people to him after his father. Usama departed Madinah on the last day of Safar, but when the army was one or two days out, word reached him that the Prophet ﷺ had fallen ill, and he camped outside the city, eventually returning to visit the Prophet ﷺ on the day of his death.