Can you re-use water used for purification–wudoo or ghusl? This issue doesn’t apply to most people unless they’re stuck somewhere without much water–like Cambodia, where they get water once a year, during flood season, and keep it for nine months.
(Before you read this, read about the three-fold categorization of water; in summary, water can either be purifying (tuhoor), pure (taahir), or impure (najas), and we can only use purifying water for wudoo and ghusl.)
Scholars agree that, if the water changes–the colour, smell, or taste change due to najaasa–then the water is najas, and you can’t use it. And water that remains free of impurity is recyclable.
But what if some najas falls into it, and it doesn’t change colour? For example, you’re washing your son/nephew/grandson, and a few drops of urine fall into your bucket of wudoo water–but the water doesn’t change in it’s three characteristics.
Is it pure?
Scholars disagree on this. Let’s blitz through some of the opinions:
Opinion 1: the water remains pure even if 100 people make wudoo with it 100,000 times–because as long as the three characteristics are the same, it’s still purifying water! They quote the following proofs:
Hadith: Water is purifying, and nothing will defile it.
Hadith: Aisha (رضالله عنها) narrates that she used some water to wash when she was in a state of janabah. The Prophet (صلي الله عليه وسلم) said: “Water does not come into the state of janabah,” i.e. it doesn’t carry impurity or become impure and remains purifying. [Musnan of Ibn Ahmad]
Hadith: Urwa ibn Mas’ood As-Sa’id met the Prophet, then said to the Quraish: “When the Messenger of Allah (صلي الله عليه وسلم) performed his wudoo, his companions rushed to share the water he used.” [Bukhari, Musnad of Imam Ahmad]
Also, the default opinion with water is that it’s purifying, until proven impure.
Opinion 2: Water becomes pure, but not purifying (like tea or coke). While it’s not najas, you can’t make wudoo or ghusl from it. They quote the following proofs:
Hadith: Don’t urinate in stagnant water and wash yourself with it.
(Meaning, even if the water looks pure, you can’t make wudoo with it.)
Opinion 3: Water already used for purifying becomes najas. (So if you make wudoo and drip water from your elbow onto your clothes, you need to re-wash them.) They use the same hadith above as proof–because one of their principles is “Any time Allah or the Prophet put two things together in a sentence, they take the same ruling.” But there are many ayaat in the Qur’an where this isn’t true, so this is a very weak proof.
So what’s the conclusion? Allahu ‘alim, scholars put forward opinion one–you can reuse wudoo water so long as it’s characteristics don’t change–because the ahadith that speak directly about this topic are many and strong; you can’t get a better proof then that.
So if a little bit of something najas falls into your bathtub or wudoo bucket, don’t freak out–remember, it’s all good! (It’s still purifying.)
Wallahu ta’ala ‘alim.
Abdul-Bary Yahya. Lecture. AlMaghrib. The Purification Act. University of Toronto, Toronto. November 2006.