Anas bin Malik reported the Prophet صلی اللہ علیہ وسلم as saying: If any one forgets a prayer or oversleeps, he should observe it when he remembers it ; there is no expiation for it except that.

Abu Hurairah reported: When the Messenger of Allah صلی اللہ علیہ وسلم returned from the Battle of Khaibar, he travelled during the night. When we felt sleep, he halted for rest. Addressing Bilal he said: Keep vigilance at night for us. But Bilal who was leaning against the saddle of his mount was dominated by sleep. Neither the Prophet صلی اللہ علیہ وسلم nor Bilal nor any of his Companions could get up till the sunshine struck them. The Messenger of Allah صلی اللہ علیہ وسلم got up first of all. The Messenger of Allah صلی اللہ علیہ وسلم was embarrassed and said: O Bilal! He replied: He who detained your soul, detained my soul, Messenger of Allah, my parents be sacrificed for you. Then they drove their mounts to a little distance. The Prophet صلی اللہ علیہ وسلم perfumed ablution and commanded Bilal who made announcement for the prayer. He (the Prophet) led them in the Fajr prayer. When he finished prayer, he said: If anyone forget saying prayer, he should observe it when he recalls it, for Allah has said (in the Quran): "Establish prayer for my remembrance". Yunus said: Ibn Shihab used to recite this verse in a similar way (i. e. instead of reciting the word li-dhikri - for the sake of My remembrance - he would recite li-dhikra - when you remember). Ahmad (one of the narrator) said: 'Anbasah (a reporter) reported on the authority of Yunus the word li-dhikri (for the sake of my remembrance). Ahmad said: The word nu'as (occurring in this tradition) means "drowsiness".

Abu Qatadah reported: "The Prophet صلی اللہ علیہ وسلم was on a journey. The Prophet صلی اللہ علیہ وسلم took a turn and I also took a turn with him. He said: 'Look!' I said: 'This is a rider; these are two riders; and these are three' until we became seven. He then said: Guard for us our prayer, i. e. the Fajr prayer. But sleep dominated them and none could awaken them except the heat of the sun. They stood up and drove away a little. Then they got down (from their mounts) and performed ablution. Bilal called for prayer and they offered two rak'ahs of (Sunnah) of Fajr and then offered the Fajr prayer and mounted (their mounts). Some of them said to others: We showed negligence in prayer. The Prophet صلی اللہ علیہ وسلم said: There is no negligence in sleep. The negligence is in wakefulness. If any of you forget saying prayer, he should offer it when he remembers it and next day (he should say it) at its proper time.

Abu Qatadah reported the Messenger of Allah صلی اللہ علیہ وسلم as saying: There is no remissness in sleep, it is only when one is awake that there is remissness when you delay saying the prayer till the time for the next prayer comes.

Narrated Abu Saeed al-Khudri: The Prophet صلی اللہ علیہ وسلم said: If anyone oversleeps and misses the witr, or forgets it, he should pray when he remembers.