The Almighty said: {And do not cast yourselves into destruction} [Quran 2:195]. The Muslims reached a consensus that he is not obligated to do this, or otherwise he would be following an action that is subject to dispute, whereas it is permissible by consensus; thus, its performance and the validity of the prayer along with it become established. Furthermore, what he mentioned is invalidated by excessive walking and running during flight or otherwise. As for the delaying of prayer on the Day of the Trench, Abu Sa'id narrated that it was before the revelation of the Fear Prayer. It is possible that the polytheists preoccupied him, so he forgot the prayer; what points to this has been transmitted, and we have mentioned it previously. This is reinforced by the fact that the Prophet (may Allah bless him and grant him peace) and his companions were not in a sword-fight that would necessitate breaking the prayer. As for shouting and ritual impurity, there is no need for them to resort to such things, and they are capable of performing Tayammum. It does not follow that because something is an invalidator when there is no excuse, it must also be an invalidator when there is an excuse, such as the discharge of impurity from a woman suffering from Istihada (prolonged non-menstrual vaginal bleeding) or one suffering from urinary incontinence. If one flees from the enemy in a permitted flight, or from a flood, a predator, or a fire, and cannot escape without fleeing, he may perform the prayer of intense fear, whether he fears for himself, his wealth, or his family. The prisoner who fears them for his life if he prays, and the one hiding in a location, both pray in whatever manner is possible for them. Ahmad stated this regarding the prisoner. If the person hiding is sitting and cannot stand, or lying down and cannot sit or move, he prays according to his ability. This is the view of Muhammad ibn al-Hasan. Al-Shafi'i said: He prays and repeats it. This is not correct because he is a fearful person who has prayed according to his ability, so repetition is not incumbent upon him, just like the one fleeing. There is no difference between residency and travel in this, because the permitting factor is the fear of destruction, and they are equal in that. Whenever it is possible to escape without that—such as the one fleeing from a flood climbing a hill, or the one afraid of an enemy being able to enter a fortress where he is safe from the enemy's assault and the occurrence of harm—he should pray therein, then leave. He would not be permitted to perform the prayer of intense fear, because it was only permitted for necessity, and therefore is confined to the presence of necessity.