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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
ahmad:4769 – Wakīʿ > ʿAbdullāh b. Nāfiʿ from his father > Ibn ʿUmar

[Machine] The Messenger of Allah ﷺ forbade castration of horses and cattle, and Ibn 'Umar said that it is a distortion of creation.  

أحمد:٤٧٦٩ – حَدَّثَنَا وَكِيعٌ حَدَّثَنَا عَبْدُ اللهِ بْنُ نَافِعٍ عَنْ أَبِيهِ عَنِ ابْنِ عُمَرَ قَالَ

نَهَى رَسُولُ اللهِ ﷺ عَنْ إِخْصَاءِ الْخَيْلِ وَالْبَهَائِمِ وقَالَ ابْنُ عُمَرَ فِيهَا نَمَاءُ الْخَلْقِ  

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Collected by Suyūṭī