• Shortly before his death, the Messenger raised an army, appointed Usama to command it, and told him to "advance only as far as the place where your father was martyred, and strengthen our rule there." The Messenger took to his bed before the army departed. When Usama visited him, the Messenger prayed for him. The army was just about to set out when the Messenger died. Abu Bakr, his political successor and the first caliph, dispatched the army without a second thought, despite uprisings in various parts of Arabia. He accompanied the soldiers to the outskirts of Madina and said: "By God, even if wolves attack us from all directions, I will not lower a flag hoisted by the Messenger." 
• The Messenger's death shocked and grieved Madina's Muslims. The subsequent election to choose the caliph caused some dissension among the Companions. Abu Bakr shouldered a very heavy task, for the army was waiting to be sent, reports of uprisings were coming in, and small groups were not satisfied with his election. Just at this juncture Fatima, the Prophet's daughter, asked him for her share in the land of Fadak. Abu Bakr did not want to offend her, but also was determined to remain faithful to the Sunna. He used to say: "I can't forsake anything that the Messenger did." He had heard something from the Messenger, which Fatima had not: "We, the community of the Prophets, do not bequeath anything. Whatever we leave is charity." 
• After the conquest of Makka, people from all over Arabia embraced Islam. Of course, many were not as devoted to Islam as the Companions. Some apostatized and, following Musaylima the Liar, revolted against Madina. Others showed signs of revolt by refusing to pay the prescribed alms-tax. Abu Bakr fought such people until peace and security reigned in Arabia once again.
• 'Umar was known as "the one who submits himself to truth." Unaware of the Prophet's decree, he put forward his own judgment about how much money should be paid to compensate someone for a cut finger. A Companion opposed him: "O Commander of the Faithful! I heard the Messenger say: 'The blood money for both hands together is the same as that paid for a life. This amount is shared out equally among the fingers, as ten camels for each.'" 'Umar instantly withdrew his ruling and said to himself: "O son of Khattab! Do you dare to judge, through your own reasoning, on a matter the Messenger decreed?"
• Abu Musa al-Ash'ari went to visit 'Umar in his office. He knocked on the door three times and then left, as he received no answer. After Abu Musa left, 'Umar opened the door and asked who had knocked. Learning that Abu Musa had knocked, 'Umar sent for him and asked why he had left. Abu Musa answered: "The Messenger said: 'When you visit someone, knock on the door. If you are not allowed to enter after you knock for the third time, go away,'" 'Umar asked him if he could verify this hadith, which was unknown to him. Abu Musa brought Abu Sa'id al-Khudri, who testified to its truth, and 'Umar conceded. 
• When 'Umar was stabbed while prostrating in the mosque, he was asked if he wanted to designate his successor. 'Umar answered: "If I designate, one who is better than me (Abu Bakr) did so. If I do not designate, one who is better than me (the Messenger) did not do so." 'Umar was certain to follow the latter action. However, to prevent any possible disagreement, he left the matter to a consultative committee that he formed for this very purpose.
• When 'Umar saw Zayd ibn Khalid al-Juhani perform a supererogatory prayer after the afternoon prayer, he reproached him for doing what the Messenger had not done. Zayd told him: "Even if you break my head into pieces, I shall never give up this two rak'ah prayer, for I saw the Messenger perform it." Umm Salama, one of the Prophet's wives, reported that one day her husband could not perform the two rak'ah supererogatory prayer after the noon prayer because he was busy with a visiting delegation. So, he prayed that prayer after the afternoon prayer. Zayd must have seen the Messenger perform it at that time.
• 'Ali once drank water while standing. Maysara ibn Ya'qub criticized him: "Why are you drinking while standing?" 'Ali answered: "If I do so, it's because I saw the Messenger do so. If I drink while sitting, it's because I saw the Messenger do so." 
• Instead of washing the feet during wudu', Muslims can wipe the upper surface of light, thin-soled boots worn indoors (or inside overshoes) with wet hands. Showing the Sunna's supremacy over personal reasoning, 'Ali said: "If I had not seen the Messenger wipe the upper surface of his light, thin-soled boots, I would deem it more proper to wipe their soles." 
• If a Muslim kills another by mistake, the killer's heirs must pay blood-money. 'Umar thought that a wife could not inherit any blood-money due to her husband. However, Dahhak ibn Abi Sufyan informed him that when Ashyam ibn Dibabi had been killed, the Messenger had given some of the blood-money to his wife. 'Umar declared: "From now on, wives will inherit from the blood-money of their husbands." 
• Abu 'Ubayda ibn Jarrah commanded the Muslim armies fighting in Syria. When 'Umar went to visit him in Amwas, pestilence had broken out already. Before 'Umar entered the city, 'Abd al-Rahman ibn al-'Awf told him: "I heard the Messenger say: 'If you hear that pestilence has broken out in a place, don't enter it. If you are in such a place already, don't leave it.'" 'Umar, so obedient to the Sunna, returned home without seeing his faithful friend for the last time.
 Bukhari, "Khums," 1; Muslim, "Jihad," 52.
 Muslim, "Adab," 7/33; Ibn Hanbal, 3:19.
 Ibn Hanbal, 1:134.
 Abu Dawud, "Tahara," 63.
 Abu Dawud, "Fara'id," 18; Ibn Ma'ja, "Diyat," 12; Tirmidhi, "Fara'id," 18.