Nasai

It is possible that intoxication develops quickly in the nabidh of busr (unripe dates), which is why Ibn Abbas (radi Allahu anhu) considered it forbidden. In any case, it is only forbidden when it becomes intoxicating; otherwise, it is not. However, the nabidh made from a mixture of busr and tamr (ripe dates) is forbidden in all circumstances, whether it becomes intoxicating or not, because the Messenger of Allah (sallallahu alayhi wa sallam) absolutely prohibited it. Although, according to the Hanafis, a mixed nabidh is permissible if it is not intoxicating, this is contrary to explicit ahadith. Opinion and analogy are blameworthy when set against textual evidence. (See also, Hadith: 5549)