The Prophet ﷺ decreed that one should not eat two dates together at a time unless he gets the permission from his companions (sharing the meal with him).

سَمِعْتُ ابْنَ عُمَرَ ؓ يَقُولُ نَهَى النَّبِيُّ ﷺ أَنْ يَقْرُنَ الرَّجُلُ بَيْنَ التَّمْرَتَيْنِ جَمِيعًا حَتَّى يَسْتَأْذِنَ أَصْحَابَهُ