Muwatta Malik, Book 20, Hadith 84 (USC-MSA)

Yahya related to me from Malik, from Ibn Shihab, from Ubaydullah ibn Abdullah ibn Utba ibn Masud, from Abdullah ibn Abbas, that as-Sab ibn Jaththama al-Laythi once gave a wild ass to the Messenger of Allah, may Allah bless him and grant him peace, while he was at al- Abwa, or Waddan, and the Messenger of Allah, may Allah bless him and grant him peace, gave it back to him. However, when the Messenger of Allah, may Allah bless him and grant him peace, saw the expression on the man's face he said, "We only gave it back to you because we are in ihram."

حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ عُبَيْدِ اللَّهِ بْنِ عَبْدِ اللَّهِ بْنِ عُتْبَةَ بْنِ مَسْعُودٍ، عَنْ عَبْدِ اللَّهِ بْنِ عَبَّاسٍ، عَنِ الصَّعْبِ بْنِ جَثَّامَةَ اللَّيْثِيِّ، أَنَّهُ أَهْدَى لِرَسُولِ اللَّهِ صلى الله عليه وسلم حِمَارًا وَحْشِيًّا وَهُوَ بِالأَبْوَاءِ أَوْ بِوَدَّانَ فَرَدَّهُ عَلَيْهِ رَسُولُ اللَّهِ صلى الله عليه وسلم فَلَمَّا رَأَى رَسُولُ اللَّهِ صلى الله عليه وسلم مَا فِي وَجْهِي قَالَ ‏ "‏ إِنَّا لَمْ نَرُدَّهُ عَلَيْكَ إِلاَّ أَنَّا حُرُمٌ ‏" ‏ ‏.‏

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also referenced under: Book 20, Hadith 788 (In-Book)