Do not eat with your left hand, for the Satan eats with his left hand.  

عَنْ رَسُولِ اللَّهِ ﷺ قَالَ لاَ تَأْكُلُوا بِالشِّمَالِ فَإِنَّ الشَّيْطَانَ يَأْكُلُ بِالشِّمَالِ  

When any one of you intends to eat (meal), he should eat with his right hand. and when he (intends) to drink he should drink with his right hand, for the Satan eats with his left hand and drinks with his left hand.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ إِذَا أَكَلَ أَحَدُكُمْ فَلْيَأْكُلْ بِيَمِينِهِ وَإِذَا شَرِبَ فَلْيَشْرَبْ بِيَمِينِهِ فَإِنَّ الشَّيْطَانَ يَأْكُلُ بِشِمَالِهِ وَيَشْرَبُ بِشِمَالِهِ  

None of you should eat with his left hand and drink with that (left hand), for the Satan eats with left hand and drinks with that (hand). Nafi' has made this addition in that:" Do not take up anything with that (left hand) and do not give anything with that" ; and in the narration transmitted on the authority of Abu Tahir there is a slight variation of wording.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لاَ يَأْكُلَنَّ أَحَدٌ مِنْكُمْ بِشِمَالِهِ وَلاَ يَشْرَبَنَّ بِهَا فَإِنَّ الشَّيْطَانَ يَأْكُلُ بِشِمَالِهِ وَيَشْرَبُ بِهَا قَالَ وَكَانَ نَافِعٌ يَزِيدُ فِيهَا وَلاَ يَأْخُذُ بِهَا وَلاَ يُعْطِي بِهَا وَفِي رِوَايَةِ أَبِي الطَّاهِرِ لاَ يَأْكُلَنَّ أَحَدُكُمْ