“Repeat the prayer,” he would be causing them to abandon an obligatory prayer; and abandoning an obligatory prayer is not permissible except for a legislated excuse that permits it. This is not such an excuse. Hence, the scholars have said: Whoever begins an obligatory act of worship is forbidden to discontinue it except for a valid excuse (1). This is not a valid excuse. The basic principle, therefore, is that their prayer is valid and that they may not leave it.

If he does not appoint a successor, they may appoint one of themselves to complete the prayer with them. If they do not do so, they should complete it individually. However, it is preferable that he appoint a successor, so that they are not confused.

Note: According to the preponderant view, there is nothing by which the follower’s prayer is invalidated merely because the imam’s prayer is invalidated, except in matters in which the imam acts on behalf of the follower. Whatever the imam performs on behalf of the follower is such that, if it is defective, the follower’s prayer is consequently defective, because that act of the imam is performed for both himself and the followers. An example is the prayer-screen: the imam’s prayer-screen serves as a prayer-screen for those behind him. Thus, if a woman passes between the imam and his prayer-screen, the imam’s prayer is invalidated, as is the followers’ prayer, because this prayer-screen is shared. For this reason, we do not instruct the follower to set up a prayer-screen; indeed, if he were to do so, he would be regarded as an excessive innovator. Thus, violating the imam’s prayer-screen constitutes a violation of the follower’s prayer-screen, and the follower’s prayer is invalidated just as the imam’s prayer is invalidated.

Here is an important principle: whoever enters into an act of worship and performs it as commanded, we do not declare it invalid except on the basis of evidence, for the basic principle is validity and discharge of one’s obligation—unless evidence establishing invalidity arises.

With the praise of Allah Most High, the second volume has ended.

It will be followed, by the will of Allah, may He be glorified and exalted, by the third volume, which begins with: “Chapter on the Description of the Prayer.”