the sale. Thus, if the seller stipulates that he may reside in the house for one month, and adds another condition—such as residing in the shop as well for one year—the condition is invalid and the sale is rendered invalid. Likewise, if the buyer stipulates that the seller carry the firewood and break it up, this is not valid and the sale is rendered invalid, because the condition is void. If the condition is void, then the portion of the price corresponding to it is unknown, which results in uncertainty regarding the price. Since knowledge of the price is a condition for a sale to be valid, the sale is invalid.

The evidence for this is the Prophet’s saying: “It is not lawful to combine a loan and a sale, nor two conditions in a sale, nor to sell what you do not possess” (1). The relevant phrase is: “nor two conditions in a sale.” Thus, if the buyer stipulates that the firewood be carried and broken up, these are two conditions in a sale; or if the seller stipulates residence in the house and the shop for a month, this is not valid. However, this argument based on this evidence is incorrect.

What is correct is that combining two conditions is permissible—indeed, even three or four conditions—according to whatever the two parties agree upon. The hadith does not indicate this in any respect. Rather, what is meant by the Prophet’s saying, “nor two conditions in a sale,” is two conditions that entail a legal prohibition. Combining the two conditions in the examples mentioned does not entail any legal prohibition, such as ignorance, injustice, usury, or the like.

It may be said: Do you not permit the buyer to stipulate that the slave be Muslim and literate? They will say: Yes.

We then say: These are two conditions in a sale, yet you say that this