Question: As salamu alaykum,Is it permissible to use impure soap?
Wa alaykum salam wa rahmatuLlahi wa barakatuHu,
Sh. Muhammad b. ‘Abd al-Rahman al-Ahdal related that one may use soap made from an impure substance to remove dirt or other filth. After using it, what it contacted must be purified. (‘Umdat al-Mufti wa al-Mustafti v. 1, p. 32)
Also, he related from Ibn Hajar that when one is uncertain about the nature of an impurity – be it najasah mughallazah [heavy impurity], najasah mutawassitah [a common impurity], or najasah mukhaffafah [light impurity] – then one should consider it mutawassitah. Therefore, if one has soap that is made from impure animal fat, for example, while being uncertain of its exact source, then he may use such soap to hygienically clean what he needs to. Following that, whatever the soap contacted should be purified, as is done for mutawassitah.
Amongst the muta’akhirin, there is a difference of opinion on a detail pertaining to purifying when using soap. Tablawi mentioned that if something is affected by an impurity, and one washes it with soap until the impurity is removed, then it is pure even if the soap’s scent remains. Differing with the view, Ramli maintained that it is not pure until one washes away the soap’s scent. (Sayyid Muhammad al-Jurdani, Fath al-‘Allam v. 1, pg. 345)
This difference does not apply here, because the impurity is actually the soap itself. Therefore, traces of the impure soap, like its scent, must be washed away. Regarding removing the traces of impurities, Khatib commented on Imam Nawawi,
وجب بعد زوال عينها إزالة الطعم وإن عسر لأن بقاءه يدل على بقاء العين ووجب محاولة إزالة غيره ولا يضر بقاء لون كلوم الدم أو ريح كرائحة الخمر عسر زواله فيطهر للمشقة بخلاف ما إذا سهل فيضر بقاؤه لدلالة ذلك على بقاء العين … فإن بقيا معا ضرا
“After removing the impure substance, it is necessary to remove its taste, even when doing so is difficult. This is for the reason that, its taste indicates that traces of the impure substance remain. And it is necessary to attempt to remove the other traces. There is no harm with some color remaining, like the color of blood. Or with some smell remaining, like the smell of wine. When removing them is difficult, then it is considered pure on account of the difficulty. On the contrary, when removing it is easy, then anything remaining is unacceptable. This is because it indicates that some of the substance remains … when both remain, that is unacceptable.” (Mughni al-Muhtaj v. 1, p. 242)
And Allah knows best.
Answered by Yaqub Abdurrahman