Prayer (Kitab Al-Salat): Voluntary Prayers
5/25. Chapter:
The (Voluntary) Night Prayer Is Performed In Units Of Two
Sunan Abi Dawud
حَدَّثَنَا الْقَعْنَبِيُّ، عَنْ مَالِكٍ، عَنْ نَافِعٍ، وَعَبْدِ اللَّهِ بْنِ دِينَارٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، : أَنَّ رَجُلاً، سَأَلَ رَسُولَ اللَّهِ صلى الله عليه وسلم عَنْ صَلاَةِ اللَّيْلِ، فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم : " صَلاَةُ اللَّيْلِ مَثْنَى مَثْنَى، فَإِذَا خَشِيَ أَحَدُكُمُ الصُّبْحَ صَلَّى رَكْعَةً وَاحِدَةً تُوتِرُ لَهُ مَا قَدْ صَلَّى " .
Narrated 'Abdullah bin 'Umar: A man asked the Messenger of Allah (ﷺ) about the prayer at night. The Messenger of Allah (ﷺ) said: Prayer during the night should consist of pairs of rak'ahs, but if one of you fears the morning is near he should pray one rak'ah which will make his prayer an odd number for him.
Reference : Sunan Abi Dawud 1326In-book reference : Book 5, Hadith 77English translation : Book 5, Hadith 1321