Hadith 5231
Jabalah bin Suhaim narrates: Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) passed by us and said: Do not eat (two dates) together, because the Noble Prophet (peace and blessings be upon him) forbade eating (two dates) together at once. However, if a person obtains permission from his brother (then the ruling is different).
Hadith 5232
Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates this statement of the Noble Prophet (peace and blessings be upon him): "Whoever is eating dates with people should not eat two dates together; if he intends to do so, he should seek their permission. If they permit him, then he may do so."