Thus, his saying, peace and blessings be upon him, “They do not purify,” indicates that istijmār performed with anything other than these two—provided it is among what may permissibly be used for istijmār—does purify.
Based on this view, which is the stronger one, if the residue spreads beyond its proper place and a person sweats into his trousers, it is not impure, because istijmār is purifying. The use of water has merely been waived as an ease for the Ummah.
These, then, are two matters whose traces are excused:
- A small amount of impure blood from an otherwise pure animal.
- The residue of istijmār in its proper place.
The apparent meaning of his words is that a small amount of anything besides these two is not excused. Thus, for example, a small amount of vomit is not excused; nor are urine and dung.
The scholars—may Allah Most High have mercy on them—have held several views on this issue (1):
The first view: A small amount is never excused.
The second view: The established position of the school is the detailed distinction mentioned above.
The third view: A small amount of all impurities is excused.
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This is the view of Abu Hanifah (2), and the preferred view of Shaykh al-Islam Ibn Taymiyyah (3), especially regarding matters to which people are frequently exposed, such as mouse droppings and dung, and the like. For avoiding them and cleansing oneself of them entails hardship. Allah Most High says:
“And He has not placed upon you in the religion any hardship.” [al-Hajj 22:78]