Fast facts
- The word
- Taharah (طهارة), cleanliness and the state of being fit to pray
- Its opposite
- Najasah (نجاسة), substantial filth; and hadath (حدث), the ritual state
- Minor purification
- Wudu (وضوء), commanded in Sūrah al-Māʾidah 5:6
- Major purification
- Ghusl (غسل), the full washing
- When water is absent
- Tayammum (تيمم), with clean earth
On this page
Two different things called impurity
English collapses into one word what Arabic keeps apart, and most confusion about this subject starts there.
- Najasah (نجاسة) is substance: filth on the body, the clothing or the ground. It is removed by cleaning the thing itself.
- Hadath (حدث) is a state, not a stain. A person who has slept or used the toilet is in it while being perfectly clean, and it is lifted by wudu (وضوء) or ghusl (غسل) rather than by washing a spot.
The distinction explains something that puzzles observers: a person who has just bathed still performs wudu before praying. They were not dirty. They were in a state that the prayer requires lifting.
Wudu (وضوء)
The obligation and its form are given in the same verse, which is unusual and useful: Sūrah al-Māʾidah 5:6 names the face, the arms to the elbows, the wiping of the head, and the feet to the ankles.
It is invalidated by what leaves the body from the two passages, by deep sleep, and by loss of consciousness. It is not invalidated by ordinary contact with dirt, which again marks the difference between hadath and najasah. Once performed, it lasts until something breaks it, so several prayers may be prayed on one wudu.
Ghusl (غسل)
Ghusl (غسل) is the washing of the whole body, obliged after marital relations, after the ending of menstruation and post-natal bleeding, and on a person entering Islam. The same verse, Sūrah al-Māʾidah 5:6, moves to it directly after wudu.
It is also recommended, without being obliged, before the Friday prayer, before the two Eids, and before entering ihram (إحرام) for hajj (الحج). The pattern is that the larger the gathering or the greater the occasion, the more the tradition presses washing on you.
When there is no water
The same verse closes the loop: if water cannot be found, or cannot be used because of illness, clean earth is struck with the hands and passed over the face and the hands. This is tayammum (تيمم), and it is a genuine substitute rather than a lesser gesture.
Why purification comes first
Open almost any classical manual of fiqh (فقه) and the first chapter is taharah, before prayer, before fasting, before anything about belief. That ordering is deliberate: the books begin where the worshipper begins, at the tap.
The Qur’an frames the outward act as tied to an inward one. Sūrah al-Baqarah 2:222 pairs those who turn back in repentance with those who purify themselves, putting the washing of the body and the cleaning of the record in the same sentence. The Prophet ﷺ (محمد) is reported as saying that purity is half of faith (Sahih Muslim 223), which is a strong claim to make about washing unless something more than hygiene is meant.
Frequently asked questions
Does wudu have to be repeated for every prayer?
No. It lasts until something invalidates it, so one wudu may serve several prayers. Renewing it for each prayer is regarded as meritorious but is not required.
Is this about hygiene?
Hygiene is a consequence rather than the purpose. A person can be entirely clean and still be required to perform wudu, and tayammum (تيمم) with clean earth lifts the state without making anyone cleaner. What is being addressed is readiness to stand before Allah, and the washing is the form that readiness takes.
What if someone has a medical condition that constantly breaks wudu?
The classical rulings treat this as a recognised category rather than an obstacle. Such a person performs wudu for the prayer time and prays, and the ongoing condition does not invalidate it. The principle is that an obligation is not imposed beyond capacity.