Sahih Muslim 508
Sahih Muslim · Book 4: The Book of Prayers · The Praying Person Standing Close To The Sutrah
Sahl b. Sa'd al-Si'idi reported:
حَدَّثَنِي يَعْقُوبُ بْنُ إِبْرَاهِيمَ الدَّوْرَقِيُّ ، حَدَّثَنَا ابْنُ أَبِي حَازِمٍ ، حَدَّثَنِي أَبِي ، عَنْ سَهْلِ بْنِ سَعْدٍ السَّاعِدِيِّ ، قَالَ كَانَ بَيْنَ مُصَلَّى رَسُولِ اللَّهِ صلى الله عليه وسلم وَبَيْنَ الْجِدَارِ مَمَرُّ الشَّاةِ .
Between the place of worship where the Messenger of Allah (ﷺ) prayed and the wall, there was a gap through which a goat could pass.