An oath concerning the private rights of individuals is given legal effect only when the judge, at the plaintiff’s request, orders the defendant to swear, and the wording must correspond exactly to the defendant’s answer to the claim. The oath must be pronounced in the judge’s courtroom.

It may be sworn only by Allah, for swearing by anything other than Allah is shirk (associating partners with Him). It suffices to invoke the Divine Name alone; if the defendant says, “By Allah,” that is adequate, for this very form of oath appears in the Quran—“They swear by Allah their strongest oaths,” “so they both swear by Allah,” and “four testimonies [sworn] by Allah.” The name Allah is a proper name for the Almighty; no one else is called by it.

The oath is intensified only in matters of major importance—such as a transgression that does not entail retaliation or the freeing of a slave—whereupon the judge may solemnize it with additional wording: “By Allah, there is no deity but Him, Knower of the unseen and the seen, the Avenger, the Irresistible, the Harmful, the Beneficial, who knows the treachery of the eyes and what hearts conceal.”

When a claim is brought by several people, the defendant must swear a separate oath to each of them, because each person’s right is independent of the others. If, however, they are content with a single oath, that one oath is sufficient, for the right is theirs and they have chosen to waive the rest.