Most of the evidence used to establish that tangible things are not prohibited by default—general scriptural texts, sound analogies, the rational presumption of continuity, and the absence of a ruling where evidence for it is absent—also establishes that contracts and their conditions are not prohibited. This holds whether they are termed lawful or left unregulated, in accordance with the familiar disagreement among our scholars and others.

For Allah Most High’s censure in the Quran of disbelievers for declaring things forbidden without revealed authority concerns, in some instances, tangible things and, in others, actions. For example, they forbade a pilgrim in a state of ritual consecration from wearing his own clothes and circumambulating in them unless he belonged to the Hums. They ordered him to strip unless a member of the Hums lent him a garment, and forbade him from going beneath a roof. Likewise, the Ansār forbade a man from having vaginal intercourse with his wife while she was bent forward, and they forbade going between al-Safā and al-Marwah.

Yet they would sometimes break covenants they had concluded without revealed authorization. Allah, glorified be He, commanded them in Surah al-Nahl and elsewhere to fulfil those covenants, except those involving something prohibited. Thus, covenants must be fulfilled if they are not prohibited, even when their lawfulness has not been established by a specific revealed ruling. Such were the covenants they concluded in the pre-Islamic age of ignorance and were commanded to fulfil.

We have already drawn attention to this principle and explained that only what Allah has prescribed may be instituted as religion, and only what Allah has forbidden may be declared forbidden. For Allah censured the polytheists who instituted religious practices He had not authorized and declared forbidden what He had not forbidden. Thus, if we declare prohibited the contracts and conditions people enter into in their customary dealings without evidence