Mishkat al-Masabih 21 Foods كتاب الأطعمة 5

وَعَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «لَا يَأْكُلَنَّ أَحَدُكُمْ بِشِمَالِهِ وَلَا يَشْرَبَنَّ بِهَا فَإِنَّ الشَّيْطَانَ يَأْكُلُ بِشِمَالِهِ وَيَشْرَبُ بهَا» . رَوَاهُ مُسلم

He reported God’s messenger as saying, “None of you must ever eat or drink with his left hand, for the devil eats and drinks with his left hand.” Muslim transmitted it.