Sahih al-Bukhari, Book 63, Hadith 75 (In-Book)

Narrated `Amr bin Maimun: During the pre-lslamic period of ignorance I saw a she-monkey surrounded by a number of monkeys. They were all stoning it, because it had committed illegal sexual intercourse. I too, stoned it along with them.

حَدَّثَنَا نُعَيْمُ بْنُ حَمَّادٍ، حَدَّثَنَا هُشَيْمٌ، عَنْ حُصَيْنٍ، عَنْ عَمْرِو بْنِ مَيْمُونٍ، قَالَ رَأَيْتُ فِي الْجَاهِلِيَّةِ قِرْدَةً اجْتَمَعَ عَلَيْهَا قِرَدَةٌ قَدْ زَنَتْ، فَرَجَمُوهَا فَرَجَمْتُهَا مَعَهُمْ‏.‏

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