How do we determine what is considered impure? Are human saliva, mucus, tears, sweat, dust, sand, and clay also considered impure? Does water become impure by mixing with a pure substance? Is it obligatory to remove dust, an unknown stain, or clay from a paper containing verses and the name of Allah? Does the persistence of such on it constitute disrespect?

If the paper is no longer usable, you should burn it or bury it in a pure place far from desecration, as stated by the Permanent Committee: "Torn masaahif (copies of the Quran)... should be buried in a good place... or burned to preserve them." However, if you wish to use it, you must remove dust and mud from it, out of reverence for the verses of Allah and His sacred symbols; "That [is so]. And whoever honors the symbols of Allah – indeed, it is from the piety of hearts." The obligation is to protect the verses of Allah from anything that suggests their desecration. As for the criterion for impurities, it refers to common practice, and it is recommended to remove impurities even if they are not ritually unclean, for the sake of complete cleanliness. Sheikh Al-Uthaymeen has drawn attention to this. Furthermore, opening the door to waswasah (obsessive whispering) concerning papers that contain verses of Allah and the like, and linking it to kufr (disbelief), leads to great evil.