Language:
كتاب الجهاد والسير
56  
Fighting for the Cause of Allah (Jihaad)
(79)
Chapter: To play with spears and other similar arms
(79)
باب اللَّهْوِ بِالْحِرَابِ وَنَحْوِهَا
Sahih al-Bukhari 2901

Narrated Abu Huraira:

While some Ethiopians were playing in the presence of the Prophet, `Umar came in, picked up a stone and hit them with it. On that the Prophet (ﷺ) said, "O `Umar! Allow them (to play)." Ma`mar (the subnarrator) added that they were playing in the Mosque.

حَدَّثَنَا إِبْرَاهِيمُ بْنُ مُوسَى، أَخْبَرَنَا هِشَامٌ، عَنْ مَعْمَرٍ، عَنِ الزُّهْرِيِّ، عَنِ ابْنِ الْمُسَيَّبِ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ قَالَ بَيْنَا الْحَبَشَةُ يَلْعَبُونَ عِنْدَ النَّبِيِّ صلى الله عليه وسلم بِحِرَابِهِمْ دَخَلَ عُمَرُ، فَأَهْوَى إِلَى الْحَصَى فَحَصَبَهُمْ بِهَا‏.‏ فَقَالَ ‏ "‏ دَعْهُمْ يَا عُمَرُ ‏"‏‏.‏ وَزَادَ عَلِيٌّ حَدَّثَنَا عَبْدُ الرَّزَّاقِ أَخْبَرَنَا مَعْمَرٌ فِي الْمَسْجِدِ‏.‏
Reference : Sahih al-Bukhari 2901
In-book reference : Book 56, Hadith 115
USC-MSA web (English) reference : Vol. 4, Book 52, Hadith 150
  (deprecated numbering scheme)