(4) باب الْقِرَانِ فِي التَّمْرِ بَيْنَ الشُّرَكَاءِ حَتَّى يَسْتَأْذِنَ أَصْحَابَهُ
Narrated Ibn `Umar:
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).
Reference: Sahih al-Bukhari 2489
In-book reference: Book 47, Hadith 7
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 3, Book 44, Hadith 669