Sahih al-Bukhari 1097
Book 18: Shortening the Prayers (At-Taqseer) · Narrated by 'Amir bin Rabi`a
Arabic
حَدَّثَنَا يَحْيَى بْنُ بُكَيْرٍ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنْ عُقَيْلٍ، عَنِ ابْنِ شِهَابٍ، عَنْ عَبْدِ اللَّهِ بْنِ عَامِرِ بْنِ رَبِيعَةَ، أَنَّ عَامِرَ بْنَ رَبِيعَةَ، أَخْبَرَهُ قَالَ رَأَيْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم وَهْوَ عَلَى الرَّاحِلَةِ يُسَبِّحُ، يُومِئُ بِرَأْسِهِ قِبَلَ أَىِّ وَجْهٍ تَوَجَّهَ، وَلَمْ يَكُنْ رَسُولُ اللَّهِ صلى الله عليه وسلم يَصْنَعُ ذَلِكَ فِي الصَّلاَةِ الْمَكْتُوبَةِ.
English translation
Narrated 'Amir bin Rabi`a:I saw the Prophet (ﷺ) on his Mount praying Nawafil by nodding his head, whatever direction he faced, but Allah's Messenger (ﷺ) never did the same in offering the compulsory prayers
Reference: Sahih al-Bukhari 1097, Book of Shortening the Prayers (At-Taqseer). English translation by Dr. Muhammad Muhsin Khan.