Jabir b. 'Abdullah al-Ansari reported that Messenger of Allah ﷺ prohibited the (preparation of) Nabidh by mixing together fresh dates and grapes, and he prohibited the preparation of Nabidh by mixing the fresh dates and unripe dates together.
عَنْ رَسُولِ اللَّهِ ﷺ أَنَّهُ نَهَى أَنْ يُنْبَذَ التَّمْرُ وَالزَّبِيبُ جَمِيعًا وَنَهَى أَنْ يُنْبَذَ الرُّطَبُ وَالْبُسْرُ جَمِيعًا