What is the jurisprudence concerning the difficulty of avoiding impurity and purifying the body and clothes during wars?

The jurisprudence of difficult matters lies in the words of Allah Almighty: "We do not burden a soul beyond its capacity." Therefore, there is no obligation with incapacity, and nothing is forbidden with necessity. The verses: "So fear Allah as much as you are able," and the Hadith: "When I command you to do something, do as much of it as you can," indicate the dropping of an obligation when one is unable to perform it, and the performance of what is possible. Jurists have stipulated rulings for ease upon those afflicted with incontinence (sals), and those for whom purifying impurity is difficult.