Hadith 802

نَا بِهِ الأَشَجُّ ، وَهَارُونُ بْنُ إِسْحَاقَ ، وَلَمْ يَذْكُرَا الرُّؤْيَةَ ، وَقَالا : عَنِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَنَّهُ كَانَ يُصَلِّي . قَالَ هَارُونُ : إِلَى رَاحِلَتِهِ ، وَقَالَ أَبُو سَعِيدٍ : إِلَى بَعِيرِهِ ، وَكَانَ ابْنُ عُمَرَ يَفْعَلُهُ
Ashaj and Harun bin Ishaq did not mention seeing in their narration; both say that (the Prophet, peace be upon him) used to pray facing his mount, and Abu Saeed says that the Prophet, peace be upon him, used to pray making his camel a sutrah (barrier), and Sayyiduna Ibn Umar, may Allah be pleased with them both, used to do the same.
Hadith Reference صحيح ابن خزيمه / جماع أبواب سترة المصلي / 802