Prayer: Touching a Forgotten Impure Object with Wetness
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 798
If a person forgets that something is impure and his wet body or clothing touches it, and while he is in the state of forgetfulness, he performs prayers with it and remembers it after prayers, his prayers are valid. However, if his wet body touches an impure object that he had forgotten was impure, and without washing himself, he performs ritual bathing (ghusl) and prayers, his ghusl and prayers are invalid unless by performing ghusl his body also becomes pure and the water does not become impure, like when ghusl is performed in running water. Furthermore, if a wet part of the body on which wuḍūʾ is performed touches an impure object that he had forgotten was impure, and before washing it he performs wuḍūʾ and prayers, his wuḍūʾ and prayer are invalid unless by performing wuḍūʾ the impure part on which wuḍūʾ is performed also becomes pure and the water does not become impure, like when wuḍūʾ is performed with kurr[1] or running water.