Riyad as-Salihin, Book 1, Hadith 623 (In-Book)

Sa'b bin Jaththamah (May Allah be pleased with him) reported: I presented a wild ass to Messenger of Allah as a gift but he returned it to me. When he perceived signs of despair on my face, he said, "I have declined to accept it because I am in the state of Ihram."[Al-Bukhari and Muslim].

وعن الصعب بن جثامة رضي الله عنه قال‏:‏ أهديت رسول الله صلى الله عليه وسلم حماراً وحشياً فرده علي، فلما رأى ما في وجهي قال‏:‏ “إنا لم نرده عليك إلا لأنا حرم” ‏(‏‏(‏متفق عليه‏)‏‏)‏

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