Narrated Sahl bin Sa`d: Abu Usaid As-Sa'di invited Allah's Messenger (ﷺ) to his wedding party and his wife who was the bride, served them on that day. Do you know what drink she gave Allah's Messenger? She had soaked some dates for him (in water) overnight, and when he had finished his meal she gave him that drink (of soaked dates).
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ أَبِي حَازِمٍ، عَنْ أَبِي حَازِمٍ، عَنْ سَهْلِ بْنِ سَعْدٍ، قَالَ دَعَا أَبُو أُسَيْدٍ السَّاعِدِيُّ رَسُولَ اللَّهِ صلى الله عليه وسلم فِي عُرْسِهِ، وَكَانَتِ امْرَأَتُهُ يَوْمَئِذٍ خَادِمَهُمْ وَهْىَ الْعَرُوسُ، قَالَ سَهْلٌ تَدْرُونَ مَا سَقَتْ رَسُولَ اللَّهِ صلى الله عليه وسلم أَنْقَعَتْ لَهُ تَمَرَاتٍ مِنَ اللَّيْلِ، فَلَمَّا أَكَلَ سَقَتْهُ إِيَّاهُ.
sunnah.com