Based on this connection between the imam’s prayer and that of the follower, the scholars of the school said: the follower’s prayer is invalidated by the invalidation of the imam’s prayer. That is, if something occurs to the imam that invalidates his prayer, both his prayer and the prayers of the followers become invalid, even if nothing that invalidates the prayer has occurred to them. No exception is made to this, except when the imam prays while in a state of ritual impurity but forgets, or is unaware of his impurity, or does not remember it until after the closing salutation. In that case, the imam must repeat the prayer, whereas the followers are not required to repeat it, even according to the school’s established position (1).

Accordingly, the author says, “There is to be no appointment of a successor”; that is, if the imam’s prayer becomes invalid, he is not to appoint someone to complete the prayer with them.

An example is an imam who loses his ritual purity during the prayer. Losing one’s ritual purity means that he relieves himself, passes wind, or experiences another act that nullifies ablution. His prayer then becomes invalid, as do the prayers of the followers, and they must repeat the prayer. But if he senses that he has lost his ritual purity and appoints a successor before his own prayer becomes invalid, this is permissible, and the followers’ prayers do not become invalid. This is because he appointed someone to complete the prayer with them before his own prayer became invalid. Since he appointed a successor for them before the prayer became invalid, his own prayer remains valid, and the replacement imam begins leading them while they are in a valid prayer and completes it with them. Thus, the author’s statement, “There is to be no appointment of a successor,” means: after the prayer has become invalid.

Another example is when a person begins the prayer and then remembers during it that he does not have ablution. His prayer was never validly established, because he is in a state of ritual impurity, and the prayer of one in such a state is not validly established. Therefore, he is not to appoint a successor; rather, the followers must begin their prayer afresh;