types of water needed for tahara and ablution

1) AT TAHOOR
It is pure in itself, has the capacity of purifying other things. [Surah Insan] “...and their Lord allowed them to drink from a type of water, or a type of drink that is tahoor…”. Ali ibn talib in the books of tafsir of ibn Katheer and others was quoted to have said that after the believers have crossed the bridge, there will be another place called kantara in which they will take an account of one another. If there are ill feelings amongst themselves or if they have wronged others, they will be instructed to a lake from which they will be told to wash their body. After that, all the fatigue faced from the land of resurrection would go away and they will have the freshness of Jannah. This lake will also purify any impurities and ill-feelings before they are allowed to head to Jannah. They will be told to drink from it, after drinking from it, whatever hard feelings that they had within their hearts will all go away.

2) AT TAAHIR

It is pure in itself, but does not have the capacity of purifying other things.

3) AN NAJIS

It is impure, Must be washed if comes on us. The strongest opinion amongst scholars is that water has only two categories. Water is either ‘Tahoor’ or ‘Najis’ . The Ulema who classified the middle category ‘At taahir’ as well say that if the water has changed in either its taste , colour or smell , it becomes taahir. If it has not changed in any of these conditions, it would be considered Tahoor. But if one of the 3 characteristics has changed by something which is impure, it will be called Najis. Looking at the middle category, ‘taahir’. If we put tea in the water and it changes the colour of the water, what do we call that?. Tea. The strongest opinion amongst the Ulema is that, this is no longer water. It is now called tea. We cannot take tea and make it a category of water because it is tea. If we add vimto to water, can we give it the name water?. No, it is juice. Because of that, they say, if water has changed in one of the 3 characteristics by something that is pure, it will take the name of that thing and it will not remain in the name of water. [Al Furqan 25:47] “And we have brought down from the heaven water that is tahoor” This tells us that you can use the rain water to lift the state of hadath.If the water has changed in taste , colour or smell but not in a  significant way, in such a way that is so settled, it is such a small change that we will still call it water and so it is still called tahoor. When the rain comes down from the heaven it goes into wells, streams and usually they get affected by their surrounding for example green colours to it, sometimes mixed with the mud and you have brown colour to it, sometimes the smell of the fruits or the leaves, some form of change will occur to it but it is so settled that it has not shifted from the name water as long as that's the case we can still use that type of water.

What about recycled water?
Regardless of water being processed or natural, if it has not changed by the 3 characteristics, it is still usable. In the absence of water? Use dust, stone or anything from the soil (tayammum). Can we use sea water? Yes. The water of the sea is tahoor, even if it is salty in taste. If we assume that there is a puddle/tub of water, and a drop of urine has dropped in that water, has it become impure? It depends if any of the three characteristics have changed or not. We must see whether any of the three characteristics have changed. If yes, it has become najis. If not, it remains pure. Hadith: The Prophet SAW said if water exceeds a certain volume two kula/containers, it will not carry impurity, meaning it will not be affected. We can assume there are many impurities in the sea (e.g bird
droppings). Due to the large volume of sea water in comparison to the impurity, the sea is not affected and remains pure. How to purify impure water?
● Adding large amount of water
● Chemical processing
● Removing najasa (a solid body) if possible.
If in doubt about the purity of water? Assume the original state of things. Everything is pure until proven otherwise. Certainty cannot be nullified with doubt/unless with a state of certainty. If in doubt and not sure, assume what we know is certain (useful in other areas of Islam as well). Similarly, if it’s original state is impure, we must assume impurity if not sure as well. For example: You made wudu in the morning and are doubtful about breaking wind later when entering the masjid. Initially you are in a state of certainty about making wudu, but then doubt came of breaking wind. We can ignore the doubt, since doubt does not nullify certainty. You can ignore the doubt. Assume that which you know is certain.

Another example: When you left home in the morning you did not have time to make wudu, so when you enter the university for example you are not sure if you did wudu at university or not. You should assume that you do not have wudu, certainty can only be nullified by certainty.

The same thing with water: You know that an amount of water was pure at some point and something happened to it making you unsure
of its purity. If it has changed in the colour, taste or smell, then you assume the original state. If you have an amount of water that you
know was impure but was then processed and you are not 100% sure whether that processing was sufficient, you should assume the certainty which is najis.

Hadith: A man once complained to the Prophet SAW and said that one will be in salah and he will feel rumbling sounds in his stomach, and he will not be sure if something has broken out or not, wind or whatever. The Prophet SAW said that one should not leave the salah. Did he smell or hear something? What happens when you smell or hear something? IT BECOMES A CERTAINTY. So the Prophet SAW is saying that the man is certain that he took wudu in the beginning, but now he is doubtful if wind has come out of him or not, The Prophet SAW said he should not leave, he should remain in the salah unless he is certain that something was smelt or was heard.

Performing Salah without wudu:

If someone realises after the prayer that they certainly did not have wudu, they must repeat the prayer, but are not sinful. It was done out of forgetfulness. Performing Salah with impurity on clothing:

If clothes have impurity on it (e.g urine) which is accidentally worn, the salah is still valid and does not need to be repeated. Hadith: The Prophet SAW lead the jamaah in salaah, and in those days they didn't have carpets so they prayed with sandals on in the mosque. SUNNAH TO PRAY WITH SANDALS ON IN AN OPEN FIELD. Inside of the salah the Prophet SAW took his sandals off, and so everyone else removed their sandals as well. After the salah the Prophet SAW asked why everyone removed their sandals, and everyone said that because we saw you O Prophet SAW remove your sandals. The Prophet SAW said that in my case Jibra’eel came down to inform me that I had impurity on my sandal(s) and that's why I removed them. Did they repeat the salah?

No, we have no narrations/reports to say that they had to repeat the salah. This means that the portion of salah that was performed by the Prophet SAW with impurity on his sandal(s) was accepted as he did it out of forgetfulness or confusion. The minute that you know, you will be required to remove the impurity. If you are in the Salah, you remove the impurity to the best of your ability e.g. remove jacket etc, but if you remove the impurity e.g. on a trouser but it reveals your awrah you will have to repeat the salah, after changing your trouser which has impurity on it. You are not allowed to perform salat with any impurity on your body, clothes or in your spot of salah. It’s an obligation for you to remove it. Out of forgetfulness it is OK. Once you remember you are obliged to remove the impurity. No free water available?

You must buy water that is tahoor. We cannot resort to tayammum if there is water available. That which is required for the fulfilment of an obligation is it itself an obligation. This is a principle of Fiqh .