Is it permissible in Islamic law to make a binding promise, through signed guarantees, a treaty, or a signed agreement, prior to the Murabaha process for a commodity?

Binding the one who promises in Murabaha to the one who commands the purchase is permissible شرعًا (Islamically), and it entails the permissibility of stipulating a seriousness margin. However, a mutual binding promise between two parties is prohibited because it is like a sales contract before ownership.

The resolution of the Islamic Fiqh Academy stated: 1. Murabaha sale to the one who commands the purchase is permissible after the commodity enters the ownership of the commanded party and after lawful possession has taken place, provided that the commanded party bears responsibility for damage or hidden defects. 2. A unilateral promise is binding religiously (diyanatan) unless there is an excuse, and legally (qada’an) if it results in a cost to the promised party. The binding nature entails fulfilling the promise or compensating for the damage. 3. A mutual promise between two parties in a Murabaha sale is permissible provided there is an option (khiyar) for one or both parties. If there is no option, it is not permissible due to its resemblance to a sale that requires the seller to own the sold item.