Is selling grape juice suitable for wine-making prohibited?
Chapter on Selling the Musarrah (Animal with milk retained in udder)
Al-Mughni
Book of Sales
Primary text
The sale of grape juice to someone known to intend making it into wine is prohibited. This ruling is based on the principle of not cooperating in sin and transgression, as stated in the Quran (Quran 5:2). Evidence includes the Prophetic tradition where the Prophet (peace be upon him) cursed ten categories of people related to intoxicants, including the seller and buyer of wine, as narrated by Ibn Abbas. The tradition narrated by Al-Tirmidhi from Anas further supports this by mentioning the curse upon all assistants in the matter. The prohibition is likened to letting someone rent one's female slave for illicit sex, as the contract is made upon the knowledge of an intended sin.
Supporting text
Al-Shafi'i disliked this practice, and some of his companions specified that the sale is prohibited only if the seller explicitly believes the buyer intends to make wine; otherwise, if there is doubt, it is merely disliked. Al-Hasan, 'Ata', and Al-Thawri permitted the sale of dates to those who make intoxicants, citing the permissibility of trade in the Quran (Quran 2:275) and the fulfillment of the sale's pillars and conditions. Al-Shafi'i also suggested that even if prohibited, the contract might remain valid because the prohibition stems from the buyer's intention/belief, similar to intentional concealment of a defect ('tadlis'), which affects the human right rather than the divine right inherent in the contract.