Types of Water and Their Rulings

The chapter on water in al-Sharh al-Mumti' establishes the foundational categories that determine whether a given water may be used for ritual purification. Ibn Uthaymin begins with a principle that is axiomatic in Islamic law: the default ruling on all water is that it is pure and purifying (tahir mutahhir), and this ruling is not removed unless there is evidence to indicate otherwise. This presumption of purity reflects a broader legal maxim — al-asl fi al-ashya' al-ibahah — applied here in the specific domain of purification.

The first and primary category is mutlaq water — absolute or unrestricted water. This is water that retains its natural character and has not been mixed with anything that would alter its description. Rain, river, sea, spring, and well water all fall into this category. Ibn Uthaymin notes the Quranic reference: "And We sent down from the sky water that is purifying" (al-Furqan 25:48). This verse, along with the prophetic statement regarding the sea — "Its water is pure and its dead are lawful" — establishes that water in its natural state is both tahir (pure itself) and mutahhir (capable of purifying others).

The second category is muqayyad water — restricted or modified water. This includes water that has been mixed with a pure substance such that it loses its name as "water" and is called by another name, such as rose water, milk, or broth. Such water is pure in itself but cannot be used for ritual purification because it is no longer what the Sharia designated when it prescribed wudu and ghusl. The scholars explain this ruling with the principle that the obligation falls on "water" specifically, and anything that can no longer be called water without qualification does not fulfill that obligation.

The third category is used water (al-ma' al-musta'mal), which is water that has been used to remove a minor hadath (i.e., water that has run off after wudu). The Hanbali position, as explained by Ibn Uthaymin, is that used water is still pure (tahir) but is no longer purifying (mutahhir) — it cannot be used again for wudu. However, Ibn Uthaymin notes that some scholars, including those in other madhabs, hold that used water retains its purifying capability, and he engages with the evidence for both positions before affirming the Hanbali view.

The fourth category is water that has become najis — impure. This occurs when a najasah (filth) falls into water and alters one of its three descriptions: color, taste, or smell. If none of these three descriptions changes, the water remains pure regardless of the quantity, according to the stronger scholarly view that Ibn Uthaymin favors. He critiques the older position that divided water into less than two qullas (approximately 190 liters) and more than two qullas as an artificial threshold unsupported by strong evidence. The operative test is change: water that has not changed remains pure.

Ibn Uthaymin also addresses the ruling on water mixed with soil, soap, or other pure substances in small quantities — the ruling is that it remains mutlaq and usable for purification as long as it can still be called water. This pragmatic approach reflects his consistent effort to make the law workable for ordinary Muslims while remaining grounded in the evidences.