Answered by Shaykh Faraz Rabbani
What should be done if you realise after you have prayed salaat that your clothes have najas on them but don’t remember exactly when your clothes became najas? Should you redo the salaat just performed? or all the ones performed in the ”najas” clothes even if that amounts to over one day?
Answer:
Walaikum assalam wa rahmatullah,
You are to legally assume that the filth affected the clothes after the prayers in such a case, given there is no clear cause that you remember.
Wassalam,
Faraz Rabbani