The governing criterion, then, is that he raises the bid without intending to buy, but rather seeking some other purpose. If the buyer suffers an excessive unfair disparity in price because of this increase—one that goes beyond what is customary—then he has the option [to rescind the sale].

Artificial bidding is prohibited, because the Prophet, peace and blessings be upon him, forbade it, saying: “Do not engage in artificial bidding.” (1) It also breeds enmity and hatred among Muslims. If people learn that someone engages in artificial bidding in order to harm buyers, they will dislike and hate him. Then, when rescission is sought on account of the unfair disparity, the seller may not agree to it, and hostility may arise between him and the buyer as well.

The third case is his statement: “the unwary buyer.” Linguistically, this is someone who readily goes along with another person and trusts what he says.

Technically, it refers to one who is ignorant of the market value and does not know how to haggle. Haggling means negotiating over the price, and it is what we commonly call bargaining. Thus, if he comes to a shopkeeper and asks, “How much is this item?” and the shopkeeper replies, “Ten riyals,” while the man does not know its value and does not know how to bargain, so he buys it for ten, then later shows it to people and they tell him, “This costs five riyals,” he says, “I did not know.” We call such a person an unwary buyer, and he has the option [to rescind the sale]. For if the item is worth five and he bought it for ten, this is an excessive unfair disparity in price that goes beyond what is customary, so he has the option. The evidence is that the Prophet, peace and blessings be upon him, said: “Whoever deceives is not of us.” (2) This is a breach of trust against Muslims, and everyone who deceives