(25) باب نَهْيِ الآكِلِ مَعَ جَمَاعَةٍ عَنْ قِرَانِ تَمْرَتَيْنِ وَنَحْوِهِمَا فِي لُقْمَةٍ إِلاَّ بِإِذْنِ أَصْحَابِهِ
Jabala b. Suhaim reported:
Ibn Zubair used to provide us with dates during the time that the people were hard pressed because of famine (Once) as we were busy in eating there happened to appear before us Ibn 'Umar. He said: Don't eat two dates together, for Allah's Messenger (ﷺ) forbade eating them together but only after seeking permission from his brother (partner). Shu'ba said: I do not think these words pertaining to seeking permission but from the words of Ibn 'Umar.
Reference: Sahih Muslim 2045 a
In-book reference: Book 36, Hadith 207
USC-MSA web (English) reference(deprecated numbering scheme): Book 23, Hadith 5075