SAEDNEWS: Clerical sources say that when a physical impurity—such as blood, urine or contaminated mud—adheres to the sole of the foot or the outer sole of a shoe, walking on dry, clean earth until the impurity is removed suffices for ritual purification; scholars differ only on the preferred distance.
According to Saed News, Shiite jurists explain that when the actual impurity (the ‘ayn of najasat), or dirt already rendered impure, is present on the sole or on the outside of footwear, it may be removed by walking on or rubbing the affected area against the ground. Several leading maraji‘—including Imam Khomeini, Saffi, Makarem, Bahjat, Fazel, Golpayegani and Araki—hold that the required distance is whatever is necessary to eliminate the impurity, recommending fifteen steps or more where feasible. Other authorities, among them Sistani, the Supreme Leader, Vahid, Zanjani, Nouri, Khui and Tabrizi, likewise require walking until the impurity is gone but advise a measure of fifteen ziraa‘ (the distance from the elbow to the tip of the middle finger), roughly ten steps or more, as preferable.
Additional practical points underline that the sole or outer shoe need not be wet to be purified by walking; dry contact with clean ground suffices. Walking will typically clean some surrounding material as well, but the interior of shoes is not purified by walking, and socks should not be considered clean by this method except in the case of durable leather-like coverings whose soles regularly contact the ground. These rulings aim to balance ritual precision with everyday practicality in cases where water is unavailable.
