Safqa (the single deal: combining two things or two contracts in one transaction, and how the lawful and the unlawful within it are treated)

Safqa is one stroke of the hand; in law it is the contract, and people who clap hands on a sale are said to have struck a deal. ¹

If a single deal joins two things that cannot be joined, such as two sisters, the contract is void for both. If it joins two things that may each be contracted, such as a sheep and a garment, the price is divided between them by value or by parts. If it joins two things neither of which may be contracted, such as wine and carrion, the contract is void by agreement. ^{1 2}

If a deal joins what may be contracted with what may not, and the unlawful part has a value, the contract stands for the lawful part by its share of the price; this is the majority view, while one Maliki view voids the whole deal. Where the unlawful part has no value, such as vinegar and wine, the Hanafis void it; the two disciples of Abu Hanifa validate it if a price is named for each; the Shafi'is and Hanbalis split the deal, validating the lawful part and voiding the unlawful. ^{2 3}

If a deal joins two contracts of different rules, such as sale and hire or sale and marriage, each stands on its own. ³