Riyad as-Salihin 159
Salamah bin Al-Akwa' (May Allah be pleased with him) reported:
My father said that a person ate in the presence of Messenger of Allah (ﷺ) with his left hand. He (ﷺ) said, "Eat with your right hand". He said, "I cannot do that." Thereupon he (the Prophet) said, "May you never do that." It was pride that prevented him from doing it. And he could not raise it (the right hand) up to his mouth afterwards. [Muslim] .
الرابع‏:‏ عن أبي مسلم، وقيل ‏:‏ أبي إياس سلمة بن عمرو بن الأكوع رضي الله عنه ، أن رجلاً أكل عند رسول الله صلى الله عليه وسلم بشماله فقال‏:‏ ‏"‏كل بيمينك‏"‏ قال‏:‏ لا أستطيع‏.‏ قال‏:‏ ‏"‏ لا استطعت‏"‏ ما منعه إلا الكبر، فما رفعها إلى فيه ‏.‏ ‏(‏‏(‏رواه مسلم‏)‏‏)‏‏.‏