to bathe inside it in order to remove major ritual impurity, that would be impermissible, because the Messenger of Allah (peace and blessings be upon him) forbade bathing in standing water that does not flow. However, as long as they bathe and perform their ablution outside the basin, there is no sin in that. The water that remains is still pure and may be used for ablution until it is exhausted, and even if its properties have altered because it has been standing for a long time, this causes no harm, God willing.
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Ablution, dry ablution, and wiping
Question: One day I fell and broke one of my legs. The doctors performed surgery, and the leg has been set with artificial bones or metal rods. Because of this, performing ablution is difficult for me, so I make dry ablution for every prayer and do not perform the regular ablution with water. Is what I am doing correct? If not, what must I do from now on, and what about the prayers I have already offered using only dry ablution?
Answer: You must wash the sound limbs and perform dry ablution for the limb that cannot be washed. If it is covered with a cast or some other barrier, you may wipe over it, and that wiping suffices instead of washing.
If there is no covering on it, yet you are unable to wash it, then after washing the sound limbs you perform dry ablution in place of that limb.
As for the prayers you performed with dry ablution alone at the beginning, you must repeat them—so long as you know their number—because dry ablution by itself does not suffice; the sound limbs must be washed.
Question: If one merely wipes over it, does that suffice without dry ablution, or must dry ablution be combined with the wiping?