I was a boy under the care of Messenger of Allah ﷺ and my hand used to go around the dish while I was eating. So Messenger of Allah ﷺ said to me, 'O boy! Mention the Name of Allah and eat with your right hand, and eat of the dish what is nearer to you." Since then I have applied those instructions when eating.  

أَنَّهُ سَمِعَ عُمَرَ بْنَ أَبِي سَلَمَةَ يَقُولُ كُنْتُ غُلاَمًا فِي حَجْرِ رَسُولِ اللَّهِ ﷺ وَكَانَتْ يَدِي تَطِيشُ فِي الصَّحْفَةِ فَقَالَ لِي رَسُولُ اللَّهِ ﷺ يَا غُلاَمُ سَمِّ اللَّهَ وَكُلْ بِيَمِينِكَ وَكُلْ مِمَّا يَلِيكَ فَمَا زَالَتْ تِلْكَ طِعْمَتِي بَعْدُ  

Eat with your right hand. He said: I cannot do that, whereupon he (the Holy Prophet) said: May you not be able to do that. It was vanity that prevented him from doing it, and he could not raise it (the right hand) up to his mouth.  

أَنَّ رَجُلاً أَكَلَ عِنْدَ رَسُولِ اللَّهِ ﷺ بِشِمَالِهِ فَقَالَ كُلْ بِيَمِينِكَ قَالَ لاَ أَسْتَطِيعُ قَالَ لاَ اسْتَطَعْتَ مَا مَنَعَهُ إِلاَّ الْكِبْرُ قَالَ فَمَا رَفَعَهَا إِلَى فِيهِ