Imam Nafi’ says that it is narrated from Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) that he was presented to the Noble Prophet (peace and blessings be upon him) at the time of the Battle of Uhud, while he was fourteen years old, but the Prophet (peace and blessings be upon him) did not permit him. Then he was presented at the time of the Battle of Khandaq at the age of fifteen, so the Prophet (peace and blessings be upon him) granted him permission.