صَحِيحُ مُسْلِمٍ
Sahih Muslim 700 d
The Book of Prayer - Travellers
It is permissible to offer voluntary prayers atop one’s mount when travelling, no matter what direction it is facing
وَحَدَّثَنَاهُ أَبُو كُرَيْبٍ، أَخْبَرَنَا ابْنُ الْمُبَارَكِ، وَابْنُ أَبِي زَائِدَةَ، ح وَحَدَّثَنَا ابْنُ نُمَيْرٍ، حَدَّثَنَا أَبِي كُلُّهُمْ، عَنْ عَبْدِ الْمَلِكِ، بِهَذَا الإِسْنَادِ نَحْوَهُ . وَفِي حَدِيثِ ابْنِ مُبَارَكٍ وَابْنِ أَبِي زَائِدَةَ ثُمَّ تَلاَ ابْنُ عُمَرَ { فَأَيْنَمَا تُوَلُّوا فَثَمَّ وَجْهُ اللَّهِ} وَقَالَ فِي هَذَا نَزَلَتْ .
This hadith has been narrated by another chain of transmitters and in the one narrated by Ibn Mubarak and Ibn Abu Za'ida (these words are narrated). Ibn 'Umar then recited: " Whether you turn thither is Allah's face," and it was revealed in this context.
Sahih Muslim, 700 dSahihصحيح