by cooking it until two-thirds of it have boiled away.
Every beverage that does not intoxicate is lawful, provided it is not consumed in the manner called muʿāqara; if muʿāqara is involved, it is impermissible. A number of scholars regard muʿāqara as gravely disliked when the drink itself is lawful, and positively forbidden when the drink is unlawful.
No one should deliberately turn wine into vinegar. Should he do so, he has acted reprehensibly; he must ask Allah’s forgiveness and may then consume it if he wishes. Others have said that he may not consume it unless it became vinegar without human intervention. This is the best-known view from Mālik, it is the opinion of ʿUmar b. al-Khattāb, and it is the view I hold. Still others maintain that it remains forbidden if a human being caused the change—unless the one who did so was a Christian.
Dates and raisins must not be combined in one nabīdh, nor may a date-based infusion be mixed with a raisin-based one. Any drink produced by combining two such ingredients—what is called al-khalitayn—is not to be drunk, though the drinker does not incur the prescribed penalty so long as a large quantity of it is non-intoxicating. The legal punishment for wine will be discussed, Allah willing, in the Book of Ḥudūd.
Because the prophetic prohibition regarding al-khalitayn did not come with the same force as the prohibition of intoxicants, drinking al-khalitayn is deemed disliked rather than strictly forbidden. Al-khalitayn is defined as bringing together two substances, each of which could be infused on its own; when combined, the drink ferments more rapidly. The ban on this mirrors the prohibition on preparing nabīdh in pitch-coated vessels.
Mālik disapproved of mixing infusions that had been prepared separately—such as a date infusion and a raisin infusion—by placing them in a single container and then drinking them together; he also disliked their being mixed even for the sake of vinegar. Whenever two varieties of dates or raisins are combined in an infusion they fall under al-khalitayn—for example, red and black raisins, the dates known as al-Ṣayḥānī and ʿajwa, or the half-ripe basr called al-maṭraq. There is no harm in drinking al-biṭʿ so long as a large amount of it does not intoxicate. Some have counted al-biṭʿ among al-khalitayn, but the first view is that of Mālik. Mālik likewise regarded the very preparation of such infusions as disliked.