Answered by Shaykh Faraz Rabbani
Consider the following:
I have dried blood on my toe but did not realise.
I am making ghusl. The place where I am making ghusl is wet already.
I wear my clothes after I finish my ghusl.
I realise a few moments later that there is blood on my toe, and this must
have existed before my ghusl started, as it is dry.
The water at the place of ghusl does not have any sign of blood.
Is the water which touched my toe najis? Hence, has the najasat spread to the rest of my foot (no signs of blood can be seen). Are my clothes najis, as when I wear them, they must touch my wet toe?
Walaikum assalam,
If your blood is from a cut, how can you be sure it is from before the ghusl? In most circumstances, you would assume that it was after it, and there is no problem.
However, if you have strong and sound reasons to believe that the blood was on your toe from before [this is unlikely, or — according to my wife — impossible: if you washed your feet, the blood would not remain dry!], then it would only be najas if it is an amount that would appear to have flowed out of the cut; any blood on a cut from which blood did not flow is pure (tahir).
If you determine that the blood was in fact najis, then only place that is najis is bloody toe itself. Everything else remains tahir, for everything is tahir until certainly proven otherwise. This is our operational certainty. Our doubts, conjectures, reasoning or musings are not enough to lift this operational certainty, for, as the fiqh principles goes, “Certainty is not lifted by doubt, but only by another certainty.”
Also: when a dry object comes into contact with a wet najas (filthy) object, we only deem the najasa to have transferred to the former if we can clearly see traces of the filth on it, its traces being colour, smell or taste.
This is obviously not the case here. Wash your toe, and forget all but Allah.
Wassalam,
Faraz.