Book of Oaths
Introduction
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Book of Oaths
The oath1 that obliges an expiation2 when the swearer breaks it is the one sworn by Allah, by one of His attributes, by the Quran, or by the mushaf (the written copy of the Quran).

Swearing by anything other than Allah is forbidden and carries no expiation.

For an expiation to become obligatory three conditions must be met:

1. The oath must be binding—that is, made deliberately about a possible future matter. If someone swears about a past event while knowingly lying, this is the ghamūs oath. Idle oaths (laghw) are those that slip from the tongue without intent—such as “No, by Allah,” or “Yes, by Allah”—as well as an oath uttered while the speaker thinks he is truthful but later learns he was mistaken; none of these require expiation.

2. The oath must be taken by choice; an oath made under duress is not binding.

3. The swearer must actually violate the oath—by doing what he swore to leave, or by omitting what he swore to do—willingly and knowingly. If he breaks it under compulsion or out of forgetfulness, no expiation is due. Likewise, whoever says, “if Allah wills,” when pronouncing an otherwise binding oath is not considered to have broken it.

It is recommended to break an oath when doing so is the better option. Whoever declares something lawful—other than his wife3—such as a slave-girl, food, clothing, or anything else—to be forbidden does not in fact make it unlawful for himself, and he is required