Ibn 'Abbas reported that Allah's Apostle ﷺ forbade the mixing of dates and grapes together, and mixing of unripe dates and ripe dates together (for preparing Nabidh), and he wrote to the people of Jurash (in Yemen) forbidding them to prepare the mixture of dates and grapes. This hadith has been narrated through another chain of transmitters with a slight variation of words.

وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا عَلِيُّ بْنُ مُسْهِرٍ، عَنِ الشَّيْبَانِيِّ، عَنْ حَبِيبٍ،
عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ نَهَى النَّبِيُّ ﷺ أَنْ يُخْلَطَ التَّمْرُ
وَالزَّبِيبُ جَمِيعًا وَأَنْ يُخْلَطَ الْبُسْرُ وَالتَّمْرُ جَمِيعًا وَكَتَبَ إِلَى أَهْلِ جُرَشَ يَنْهَاهُمْ عَنْ خَلِيطِ
التَّمْرِ وَالزَّبِيبِ .