Sunan Ibn Majah, Volume 4, Book 29, Hadith 3264 (DarusSalam) ⓘ

It was narrated that ‘Aishah said: “The Messenger of Allah was eating food with six of his Companions when a Bedouin came and ate it all in two bites. The Messenger of Allah said: ‘If he had said Bismillah, it would have sufficed you (all). When any one of you eats food, let him say Bismillah, and if he forgets to say Bismillah at the beginning, let him say Bismillah fi awwalihi wa akhirih (In the Name of Allah at the beginning and at the end).’”

حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا يَزِيدُ بْنُ هَارُونَ، عَنِ هِشَامٍ الدَّسْتَوَائِيِّ، عَنْ بُدَيْلِ بْنِ مَيْسَرَةَ، عَنْ عَبْدِ اللَّهِ بْنِ عُبَيْدِ بْنِ عُمَيْرٍ، عَنْ عَائِشَةَ، قَالَتْ كَانَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ يَأْكُلُ طَعَامًا فِي سِتَّةِ نَفَرٍ مِنْ أَصْحَابِهِ فَجَاءَ أَعْرَابِيٌّ فَأَكَلَهُ بِلُقْمَتَيْنِ فَقَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ ‏ "‏ أَمَا أَنَّهُ لَوْ كَانَ قَالَ بِسْمِ اللَّهِ لَكَفَاكُمْ فَإِذَا أَكَلَ أَحَدُكُمْ طَعَامًا فَلْيَقُلْ بِسْمِ اللَّهِ فَإِنْ نَسِيَ أَنْ يَقُولَ بِسْمِ اللَّهِ فِي أَوَّلِهِ فَلْيَقُلْ بِسْمِ اللَّهِ فِي أَوَّلِهِ وَآخِرِهِ ‏" ‏ ‏.‏