He heard the Messenger of Allah ﷺ say, "Do not combine fresh dates with partially ripened ones, nor raisins with dried dates. Steep each of them separately."
حدثنا هشام بن عمار حدثنا الوليد بن مسلم حدثنا الأوزاعي عن يحيى بن أبي كثير
أنه سمع رسول الله ﷺ يقول لا تجمعوا بين الرطب والزهو ولا بين الزبيب والتمر وانبذوا كل واحد منهما على حدته
Bukhari narrated it in the Book of Drinks, Chapter on Those Who Held That Fresh Dates and Dried Dates Should Not Be Mixed If It Causes Intoxication, etc., no. 5602, from Hisham bin Ammar, and Muslim, in the Book of Drinks, Chapter on the Dislike of Steeping Dried Dates and Raisins Together, no. 1988/24, from the hadith of Yahya through this same chain.