Reported in Sahih Bukhari:
Volume 001, Book 010, Hadith Number 569.
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Narated By 'Abdullah bin Abi Qatada : My father said, "One night we were travelling with the Prophet and some people said, 'We wish that Allah's Apostle would take a rest along with us during the last hours of the night.' He said, 'I am afraid that you will sleep and miss the (Fajr) prayer.' Bilal said, 'I will make you get up.' So all slept and Bilal rested his back against his Rahila and he too was overwhelmed (by sleep) and slept. The Prophet got up when the edge of the sun had risen and said, 'O Bilal! What about your statement?' He replied, 'I have never slept such a sleep.' The Prophet said, 'Allah captured your souls when He wished, and released them when He wished. O Bilal! Get up and pronounce the Adhan for the prayer.' The Prophet performed ablution and when the sun came up and became bright, he stood up and prayed."
Reported in Sahih Muslim:
Book 004, Hadith Number 1448.
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Chapter : The excellence of Qunut in all the prayers when any calamity befalls the Muslims.
Abu Huraira reported that when the Messenger of Allah (may peace be upon him) returned from the expedition to Khaibar, he travelled one night, and stopped for rest when he became sleepy. He told Bilal to remain on guard during the night and he (Bilal) prayed as much as he could, while the Messenger of Allah (may peace be upon him) and his Companions slept. When the time for dawn approached Bilal leaned against his camel facing the direction from which the dawn would appear but he was overcome by sleep while he was leaning against his camel, and neither the Messenger of Allah (may peace be upon him) nor Bilal, nor anyone else among his Companions got up, till the sun shone on them. Allah's Messenger (may peace be upon him) was the first of them to awake and, being startled, he called to Bilal who said: Messenger of Allah I may my father and mother be offered as ransom for thee, the same thing overpowered me which overpowered you. He (the Holy Prophet, then) said: Lead the beasts on: so they led their camels to some distance. The Messenger of Allah (may peace be upon him) then performed ablution and gave orders to Bilal who pronounced the Iqama and then led them in the morning prayer. When he finished the prayer he said: When anyone forgets the prayer, he should observe it when he remembers it, for Allah has said: "And observe the prayer for remembrance of Me" (Qur'an. xx. 14). Yunus said: Ibn Shilab used to recite it like this: "(And observe the prayer) for remembrance."