What are the prerequisites for the validity of Li'an (mutual imprecation)?
General Chapter
Al-Mughni
Book of Mutual Imprecation (Li'an)
Primary text
The validity of Li'an requires six conditions. First, it must occur in the presence of the Imam (ruler/judge) or their deputy. Second, each party must deliver their imprecation only after the Imam pronounces it upon them; premature utterance invalidates the process, analogous to taking an oath before the judge administers it. Third, all five prescribed pronouncements of Li'an must be completed; omission of even one invalidates the act. Fourth, the specific wording must be used, except where there is scholarly disagreement concerning the substitution of a phrase with one of equivalent meaning. Fifth, the sequence must be strictly observed; if the curse pronouncement precedes any of the other four phrases, or if the wife precedes the husband in delivering her Li'an, it is not considered valid. Sixth, each party must point to the other if they are present, or name and attribute the accusation if the other party is absent.
Supporting text
It is not required that both parties be physically present together during the Li'an. If one party is absent from the other, such as the husband imprecating in the mosque while the wife does so at the door because of an impediment preventing her entry, the Li'an is permissible.