is part of the response to an implied oath. The meaning is: “By Allah, you must surely straighten [your] rows.” Thus, the sentence is reinforced by three forms of emphasis: the oath, the lām, and the emphatic nūn. This is a statement containing a warning, for he said, “You must surely straighten your rows, or Allah will cause your faces to differ,” meaning, your viewpoints will differ until your hearts become divided. Without doubt, this is a threat against whoever neglects to straighten the row. Hence, some scholars held that straightening the row is obligatory. (1) They cited as evidence the Prophet’s command to do so and his warning against مخالفة (going against it). Anything that is commanded and whose contravention is threatened against cannot be described as merely a sunnah.

Therefore, the stronger view in this matter is that straightening the row is obligatory, and that if the congregation does not straighten the row, they are sinful. This is also the apparent position of Shaykh al-Islam Ibn Taymiyyah (may Allah have mercy on him). (2) But if they go against this and do not straighten the row, is their prayer invalidated because they have omitted an obligatory matter?

The answer is that there is a possibility that it is invalidated, on the grounds that they have omitted an obligation. However, the likelihood that the prayer remains valid while they are sinful is stronger, because straightening the row is obligatory for the prayer, rather than an obligation within the prayer itself—that is, it lies outside its essential form. Whoever neglects something obligatory for the prayer is sinful, but the prayer is not invalidated by its omission, as with the adhan, for example: it is obligatory for the prayer, yet the prayer is not invalidated by omitting it.

Straightening the row means ensuring alignment, so that no one stands ahead of another. Is what is considered the front of the foot? The answer is that the reference points are the shoulders in the upper part of the body and the ankles in the lower part of the body. This applies when people are standing upright. But if a person has a hunched back, the shoulders are not taken into account, because it is not possible