Is ablution by means of Tayammum permissible if a person has impurity upon their body and is unable to wash it due to lack of water or fear of harm from using it?
Chapter on Tayammum
Al-Mughni
Book of Purification
Primary text
If impurity is present on the body and washing is impossible due to the absence of water or the risk of harm from its use, performance of Tayammum and prayer is obligatory. Ahmad holds that this situation is analogous to a person in a state of major ritual impurity (Janabah) who performs Tayammum. This view is reported from Hasan, Al-Awza'i, Al-Thawri, and Abu Thawr. The evidence supporting this ruling includes the saying of the Prophet, peace be upon him: "The pure earth is the ablution of the Muslim, even if he does not find water for ten years," and his saying: "The earth has been made a place of prayer and purification for me." This is justified because it is a purification required upon the body for the sake of prayer, thus Tayammum may substitute for it when water is unavailable or harmful, similar to ritual impurity. Furthermore, Tayammum substitutes for ritual impurity purification even when applied to a part of the body other than the face and hands (like a wound), which contrasts with washing.
Supporting text
Some scholars, including Al-Qadi, interpret Ahmad's statement as meaning the person prays according to their current state, like one in Janabah performing Tayammum. This is the position of the majority of jurists, who argue that the prescribed texts (Shari'ah) regarding Tayammum pertain only to ritual impurity (Hadath), not the removal of physical impurity (Najasah), as removal targets the specific location of the impurity and cannot be achieved through Tayammum.