Animal-derived ingredients in non-food products
Question

It was mentioned in question 210 that their was a difference of scholarly opinion concerning the use of animal-derived ingredients in non-food products such as lotions and soaps and whether we as Muslims can use these products. I wanted to know if you could clarify this point and the meaning of the ayah and hadiths that follow: "Say (O Muhammad): "I find not in that which has been inspired to me anything forbidden to be eaten by one who wishes to eat it, unless it be Maytah (a dead animal) or blood poured forth..." 6:145   the hadith: Jabir b. Abdullah (RAA) reported Allah's Messenger (S) as saying in the Year of Victory while he was in Mecca: Verily Allah and His Messenger have forbidden the sale of wine,carcass,swine,and idols. It was said: Allah's Messenger, you see that the fat of the carcasss is used for coating the boats and varnishing the hides and people use it for lighting purposes, whereupon he said: No, it is forbidden. Then Allah's Messenger (S) said: May Allah the Exalted and Majestic destroy the Jews; when Allah forbade the use of fat of the carcass for them, they melted it,and then sold it and made use of its price (received from it). [Sahih Muslim Eng. Trans. Vol. 3 Hadith 3840]   The freed slave girl of Maimuna was given a goat in charity but it died. The Messenger of Allah (S) happened to pass by that (carcass). Upon this he said: Why did you not take off its skin? You could put it to use, after tanning it. They (the Companions) said: It was dead. Upon this he (the Messenger of Allah) said: Only its eating is prohibited. [Sahih Muslim Eng. Trans. Vol. 1 Haidith 704].
Praise be to Allah.Firstly: 
With regard to the ruling on using fats from haraam animals in manufacturing soap etc., we have mentioned in the question referred to that there is a difference of scholarly opinion, but it is most likely the case that they are haraam and we are not allowed to use them. 
We will explain this further – in sha Allah – in the following points. 
Secondly: 
With regard to the verse (interpretation of the meaning): 
“Say (O Muhammad): ‘I find not in that which has been revealed to me anything forbidden to be eaten by one who wishes to eat it, unless it be Maytah (a dead animal) or blood poured forth (by slaughtering or the like), or the flesh of swine (pork); for that surely, is impure or impious (unlawful) meat (of an animal) which is slaughtered as a sacrifice for others than Allaah (or has been slaughtered for idols, or on which Allaah’s Name has not been mentioned while slaughtering). But whosoever is forced by necessity without wilful disobedience, nor transgressing due limits; (for him) certainly, your Lord is Oft‑Forgiving, Most Merciful’”
[al-An’aam 6:145]
its meaning is as follows: 
“Say (O Muhammad): ‘I find not in that which has been revealed to me anything forbidden to be eaten” – Here Allaah is commanding His slave and Messenger Muhammad (peace and blessings of Allaah be upon him): Say, O Muhammad, my Lord has not forbidden any foods apart from these; everything else is halaal (permissible). 
“unless it be Maytah (a dead animal)” this refers to whatever dies a natural death, such as an animal that is dealt a fatal blow, falls or is gored by another, or that which is slaughtered in a manner other than that which is prescribed in sharee’ah. 
“or blood poured forth (by slaughtering or the like)” means blood that flows, unlike other things that are described as “blood” (damm), such as the liver and spleen, and unlike the blood which remains in the flesh and veins after slaughter. 
“or the flesh of swine (pork)” which is the well known animal (pig). 
“for that surely, is impure” means it is filthy, abominable and harmful. 
“or impious (unlawful) meat (of an animal) which is slaughtered as a sacrifice for others than Allaah (or has been slaughtered for idols, or on which Allaah’s Name has not been mentioned while slaughtering)” means, it has been slaughtered in a name other than His. 
“But whosoever is forced by necessity” to eat one of the things mentioned here, “without wilful disobedience” not wanting to eat it without being forced to, “nor transgressing due limits” – “(for him) certainly, your Lord is Oft‑Forgiving, Most Merciful” means, He will forgive him for what he has eaten, and will be Merciful towards him. 
However, we should note that there are other haraam things which are not mentioned in this verse. They were forbidden later on, such as every wild animal that has fangs and every bird that has talons, and the meat of domestic donkeys. 
Thirdly: 
The hadeeth of Jaabir was narrated by al-Bukhaari (2121) and Muslim (1581). 
The wording is as follows: It was narrated from Jaabir ibn ‘Abd-Allaah (may Allaah be pleased with him) that he heard the Messenger of Allaah (peace and blessings of Allaah be upon him) say on the day of the Conquest when he was in Makkah: “Allaah and His Messenger have forbidden the sale of alcohol, dead meat, pigs and idols.” It was said, “O Messenger of Allaah, what do you think of the fat taken from a dead animal which is used for caulking ships, greasing animal skins and which people use to light their lamps?” He said, “No, it is haraam.” Then the Messenger of Allaah (peace and blessings of Allaah be upon him) said, “May Allaah curse the Jews, for Allaah forbade them the fat, but they melted it then they sold it and consumed its price.” 
With regard to the meaning: 
It is clear that the context is explaining the prohibition on selling alcohol (khamr – that which fogs (khaamara) the mind – which includes all kinds of alcohol), dead meat, pigs and idols – which are things made from wood, copper, gold, etc, in the form of people or animals. 
Then the Sahaabah wanted to make an exception from this prohibition in the case of selling the fat of dead animals, because of the benefits that there were in it, which that it was used as caulking for ships, to protect the wood from water, and to grease animal skins in order to keep them soft and supple, and as fuel for lamps. 
The Prophet (peace and blessings of Allaah be upon him) did not make these things exceptions from the prohibition, as he said, “No, it is forbidden.” Then he mentioned what the Jews did, which was that they melted down the fat that Allaah has forbidden to them, and turned it into another substance, such as wax, which they then sold and consumed its price.
The scholars differed as to what the pronoun huwa (it) in the Prophet’s phrase Laa, huwa haraam (No, it is forbidden) referred. Some of them said that what is haraam is benefitting from the thing; others said that what is haraam is selling it. The latter view is the one which was regarded as correct by Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him), who said in al-Sharh al-Mumti’ (8/136): 
“This view is the one which is correct: that the pronoun in the phrase ‘it is forbidden’ refers to selling, even though the substance in question has these uses that the Sahaabah (may Allaah be pleased with them) mentioned. That is because the context of the hadeeth has to do with selling. 
And it was said that ‘it is forbidden’ refers to benefitting from it in these ways, so it is not permissible to caulk ships with it, or grease animal skins with it, or to use it in people’s lamps. But this view is da’eef (weak). 
The correct view is that it is permissible to caulk ships with it, and grease animal skins, and use it in people’s lamps.” 
Al-San’aani said: 
The pronoun in the phrase ‘it is forbidden’ is to be understood as referring to selling, i.e., that selling the fat is haraam. This is the most apparent meaning, because this is what is implied by the context, and because the same hadeeth was narrated by Ahmad, in whose version it says, ‘And what do you think of selling the fat of dead meat?’ Or it may be interpreted as referring to the uses to which it is put, in the phrase, ‘for it is used for caulking ships’ etc.. The majority interpreted it in this manner and said, ‘No use should be made of a dead animal apart from its skin, if it is tanned.’ 
Those who say that the pronoun refers to selling quote as evidence the fact that there is scholarly consensus that it is permissible to feed dead meat to dogs even if they are hunting dogs. It is known that the pronoun is more likely to refer to selling, so it is permissible to make use of naajis (impure) things in general and it is haraam to sell them for the reasons that are known. This view is supported by the fact that the Prophet (S) condemned the Jews for melting down the fat then selling it and consuming its price. So it is clear that the prohibition is directed against the selling which results in the consumption of its price. If the prohibition applies to selling then it is permissible to make use of the fat of dead animals and impure (naajis) fats for all purposes except food for humans or use on human bodies. (i.e., it is not permissible for a human being to eat the fat from a dead animal or to apply impure (naajis) fats to his body). So the prohibition is like the prohibition on eating dead meat or using impure substances on the body. But it is permissible to feed the fat of dead animals to dogs or to feed honey that is contaminated with an impure substance to bees. All of that is regarded as permissible in the Shaafa’i madhhab, and was narrated by al-Qaadi ‘Iyaad from Maalik and most of his companions, and from Abu Haneefah and his companions, and from al-Layth. 
This hadeeth also indicates that if it is haraam to sell a thing, its price is also forbidden, and that every contrivance that leads to permitting something which is forbidden is false.
Subul al-Salaam, 3/6. 
Fourthly: 
With regard to the hadeeth of Maymoonah, it was narrated by al-Bukhaari (1421) and Muslim (363). The following version is quoted from Muslim because the version narrated by al-Bukhaari does not contain the word “tanning”. 
It was narrated that Ibn ‘Abbaas said: A sheep was given in charity to the freed slave woman of Maymoonah, and it died. The Messenger of Allaah (peace and blessings of Allaah be upon him) passed by it and said: “Why do you not take its skin, tan it and make use of it?” They said, “It is dead meat.” He said, “It is only haraam to eat it.” 
With regard to its meaning: 
Maymoonah had a freed slave woman who had a sheep that someone had given to her in charity. When it died, they thought that it was not permissible to make any use of it at all, so they threw it away. The Messenger of Allaah (peace and blessings of Allaah be upon him) passed by it with some of his companions and when he saw it, he said to them “Why do you not take the skin of this dead animal and make use of it?” They said to him, “It is dead meat.” The Prophet (peace and blessings of Allaah be upon him) said to them, “What is forbidden is to eat it; with regard to anything other than eating it, such as making use of the skin, that is permissible after tanning it.” 
The scholars differed concerning the ruling on the skin of dead animals if it is tanned.  Shaykh Ibn ‘Uthaymeen favoured the view that tanning purifies the skin of the dead animal if it is from an animal whose meat may be eaten, such as camels, cattle and sheep. But if it comes from an animal whose meat may not be eaten, such as pigs, then it cannot be purified by tanning.
Al-Sharh al-Mumti’, 1/72.
 Shaykh al-Islam said, after quoting the views of the scholars: 
The point of confusion has to do with tanning: is it the case that the skin of animals which pure when they are alive may be purified by tanning when they are dead or is it the case that tanning can only purify the skin of an animal that is slaughtered properly according to sharee’ah? The second opinion is more likely to be correct, and the evidence for that is that the Prophet (peace and blessings of Allaah be upon him) forbade using the skin of carnivores, as was narrated by Usaamah ibn ‘Umayr al-Dhuhali.  Narrated by Ahmad, Abu Dawood, and al-Nasaa’i. Al-Tirmidhi added the phrase “and (he forbade) their use as furnishing.”  
This opinion reconciles all the ahaadeeth .  
Majmoo’ al-Fataawa, 21/95-96 
And Allaah knows best.