Categories of Water

Purification (ṭahāra) is of two kinds: purification by water — which is wuḍūʾ, ghusl and the removal of impurity — and purification by earth, which is tayammum. The question: which water may we use for purification? Water falls into four categories.

1. Pure and purifying water (ṭāhir muṭahhir): this is *al-māʾ al-muṭlaq* (unqualified water) — pure in itself and in its essence, not impure; purifying for other than itself; valid for both customary uses and acts of worship. Customs include perfuming and cleaning the house; worship includes wuḍūʾ, ghusl and the removal of impurity. It is the water that remains on its original creation, i.e. it has not changed. Its examples: sea water — which descended from the sky or sprang from the earth — melted snow/ice water, well water and spring water. This water alone, together with the pure-but-disliked water, is the water we may perform wuḍūʾ with.

Change: water changes through its colour, taste or smell. If one of these three attributes changes, it becomes 'changed' (mutaghayyir); then we look: by what did it change — by something pure or by an impurity?

2. Pure but not purifying (ṭāhir ghayr muṭahhir): water that is pure in itself but not purifying for other than itself; valid for customs but not for worship. It changed by something pure but is not purifying, so it is not used for ghusl. Its examples: soap and shampoo — its name has become 'changed', and it is not permissible to bathe with it. So the changed water — the one whose three attributes have been altered — has the ruling of pure but not purifying.

Exceptions: (hardship brings ease). Unless the water changed by something from which it is customarily difficult to protect it; then it keeps the ruling of unqualified water. Like the spring of Korbous, or the spring water that runs from red clay — here the clay customarily accompanies the water and cannot be separated from it. Likewise well water sometimes has a smell. And sometimes tap water carries the smell of chlorine, changed by something in its passage that is difficult to protect the water from; but if it becomes yellow, that we do not use.

3. Impure (najis): an impurity touched it and changed it; this water is used neither for customs nor for worship. Here it is not considered whether it is much or little. However, if a single drop of impurity falls without changing the water, nothing is upon it, and it remains pure and purifying. Likewise sea water, because it is renewed, and well water.

The rule: the ruling of the water is the ruling of what changed it.

4. Pure and purifying but disliked (ṭāhir muṭahhir makrūh): it is disliked when other water is available. Its two examples: used water (al-māʾ al-mustaʿmal) — water you performed wuḍūʾ with and then collected — and water heated by the sun in a metal vessel in a hot country.

A note: the condition is not part of the act; rather it is a condition for the act to be valid.