Hadithcore
Sunan Ibn Majah, 1176
da’if· Darussalam

A man asked Ibn ‘Umar:

“How should I perform Witr?” He said: “Pray Witr with one Rak’ah.” He said: “I am afraid that the people will say that I am cutting the prayer short.” He said: “The Sunnah of Allah and His Messenger.” Meaning “This is the Sunnah of Allah and His Messenger.”

حَدَّثَنَا عَبْدُ الرَّحْمَنِ بْنُ إِبْرَاهِيمَ الدِّمَشْقِيُّ، حَدَّثَنَا الْوَلِيدُ بْنُ مُسْلِمٍ، حَدَّثَنَا الأَوْزَاعِيُّ، حَدَّثَنَا الْمُطَّلِبُ بْنُ عَبْدِ اللَّهِ، قَالَ سَأَلَ ابْنَ عُمَرَ رَجُلٌ فَقَالَ كَيْفَ أُوتِرُ قَالَ أَوْتِرْ بِوَاحِدَةٍ ‏.‏ قَالَ إِنِّي أَخْشَى أَنْ يَقُولَ النَّاسُ الْبُتَيْرَاءُ فَقَالَ سُنَّةُ اللَّهِ وَرَسُولِهِ ‏.‏ يُرِيدُ هَذِهِ سُنَّةُ اللَّهِ وَرَسُولِهِ ـ صلى الله عليه وسلم ـ ‏.‏

References2 variants
In-Book Reference
Book 5, Hadith 374
English Reference
Vol. 1, Book 5, Hadith 1176