The third is a “conditional formula,” such as saying: “If you enter the house, you are divorced.” This is called divorce contingent upon a condition. The speaker may intend to swear an oath, while disliking the prospect of divorce taking effect if the condition is fulfilled; alternatively, he may intend divorce to take effect when the condition is fulfilled.

The first case has the same ruling as an oath invoking divorce, by agreement of the jurists. If someone says, “If I swear an oath, I must free a slave,” and then swears an oath invoking divorce, he has broken his oath, with no disagreement known to us among the recognized scholars. The same applies to all other conditional statements intended as oaths, such as: “If I do such-and-such, I must free a slave,” “then my slaves are free,” “then I must perform Hajj,” “then I must fast for a month,” or “then my wealth is to be given in charity or as a sacrificial offering,” and similar statements. These are equivalent to saying: “Freeing a slave shall be binding upon me: I will not do such-and-such,” or “Hajj shall be binding upon me: I will not do such-and-such,” and similar statements. However, what comes last in the conditional formula comes first in the oath formula, and what is negated in one formula is affirmed in the other.

The second case is where the speaker intends divorce to take effect upon fulfillment of the condition. According to the generality of early and later scholars, divorce takes effect when that condition is fulfilled, just as an immediate pronouncement of divorce takes effect. The same applies if he specifies a time for divorce, saying, for example: “You are divorced at the beginning of the month.” More than one scholar has reported consensus that such a conditional divorce takes effect, and no early disagreement concerning it was known. Ibn Hazm, however, claimed that divorce does not take effect through it, which is also the position of the Imāmī Shia—even though Ibn Hazm himself reported in his Book of Consensus that the scholars agreed that divorce does take effect through it.