Sahih al-Bukhari 2489
Sahih al-Bukhari · Book 47: Partnership · A partner should not eat two dates at a time
Narrated Ibn `Umar:
حَدَّثَنَا خَلاَّدُ بْنُ يَحْيَى ، حَدَّثَنَا سُفْيَانُ ، حَدَّثَنَا جَبَلَةُ بْنُ سُحَيْمٍ ، قَالَ سَمِعْتُ ابْنَ عُمَرَ ـ رضى الله عنهما ـ يَقُولُ نَهَى النَّبِيُّ صلى الله عليه وسلم أَنْ يَقْرُنَ الرَّجُلُ بَيْنَ التَّمْرَتَيْنِ جَمِيعًا، حَتَّى يَسْتَأْذِنَ أَصْحَابَهُ.
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).