عَنْ أَبِي أَيُّوبَ الْأَنْصَارِيِّ رَضِيَ اللَّهُ عَنْهُ أَنَّهُ قَالَ كُنَّا عِنْدَ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ يَوْمًا فَقُرِّبَ طَعَامًا فَلَمْ أَرَ طَعَامًا كَانَ أَعْظَمَ بَرَكَةً مِنْهُ أَوَّلَ مَا أَكَلْنَا وَلَا أَقَلَّ بَرَكَةً فِي آخِرِهِ قُلْنَا كَيْفَ هَذَا يَا رَسُولَ اللَّهِ قَالَ لِأَنَّا ذَكَرْنَا اسْمَ اللَّهِ عَزَّ وَجَلَّ حِينَ أَكَلْنَا ثُمَّ قَعَدَ بَعْدُ مَنْ أَكَلَ وَلَمْ يُسَمِّ فَأَكَلَ مَعَهُ الشَّيْطَانُ
Sayyiduna Abu Ayyub Ansari (may Allah be pleased with him) narrates that one day we were with the Noble Prophet (peace and blessings be upon him), and food was presented before him. I have not seen any food that was more blessed at the beginning than it, but at the end, I have not seen any food with less blessing than it. We asked: O Messenger of Allah! How is this? He replied: The reason is that when we began eating it, we mentioned the name of Allah Almighty, but later those who sat down to eat did not say Bismillah, so Satan sat with them.