Is L-cysteine that is derived from human or animal sources halal?

Sources

• ✓ 2:173 · Al-Baqara

  2:173 · Muhammad Marmaduke Pickthall

  إِنَّمَا حَرَّمَ عَلَيْكُمُ ٱلْمَيْتَةَ وَٱلدَّمَ وَلَحْمَ ٱلْخِنزِيرِ وَمَآ أُهِلَّ بِهِۦ لِغَيْرِ ٱللَّهِ ۖ فَمَنِ ٱضْطُرَّ غَيْرَ بَاغٍۢ وَلَا عَادٍۢ فَلَآ إِثْمَ عَلَيْهِ ۚ إِنَّ ٱللَّهَ غَفُورٌۭ رَّحِيمٌ

  He hath forbidden you only carrion, and blood, and swineflesh, and that which hath been immolated to (the name of) any other than Allah. But he who is driven by necessity, neither craving nor transgressing, it is no sin for him. Lo! Allah is Forgiving, Merciful.

• ✓ 5:5 · Al-Maaida

  5:5 · Muhammad Marmaduke Pickthall

  ٱلْيَوْمَ أُحِلَّ لَكُمُ ٱلطَّيِّبَٰتُ ۖ وَطَعَامُ ٱلَّذِينَ أُوتُوا۟ ٱلْكِتَٰبَ حِلٌّۭ لَّكُمْ وَطَعَامُكُمْ حِلٌّۭ لَّهُمْ ۖ وَٱلْمُحْصَنَٰتُ مِنَ ٱلْمُؤْمِنَٰتِ وَٱلْمُحْصَنَٰتُ مِنَ ٱلَّذِينَ أُوتُوا۟ ٱلْكِتَٰبَ مِن قَبْلِكُمْ إِذَآ ءَاتَيْتُمُوهُنَّ أُجُورَهُنَّ مُحْصِنِينَ غَيْرَ مُسَٰفِحِينَ وَلَا مُتَّخِذِىٓ أَخْدَانٍۢ ۗ وَمَن يَكْفُرْ بِٱلْإِيمَٰنِ فَقَدْ حَبِطَ عَمَلُهُۥ وَهُوَ فِى ٱلْءَاخِرَةِ مِنَ ٱلْخَٰسِرِينَ

  This day are (all) good things made lawful for you. The food of those who have received the Scripture is lawful for you, and your food is lawful for them. And so are the virtuous women of the believers and the virtuous women of those who received the Scripture before you (lawful for you) when ye give them their marriage portions and live with them in honour, not in fornication, nor taking them as secret concubines. Whoso denieth the faith, his work is vain and he will be among the losers in the Hereafter.

• ✓ Tafsir Ibn Kathir on 2:173

  Sunni

  Tafsir Ibn Kathir · 2:173

  Allah Almighty commands His believing servants to eat of the good and pure provisions He has provided for them and to be grateful to Him if they truly serve Him. Consuming lawful (halal) food is a cause for acceptance of supplications and acts of worship, whereas eating from the unlawful (haram) prevents acceptance of prayers and devotion. This is supported by the hadith narrated by Imam Ahmad from Abu Huraira, in which the Prophet ﷺ said: "O people, Allah is pure and accepts only that which is pure. He commanded the believers as He commanded the messengers, saying: 'O messengers, eat from the good things and do righteous deeds; indeed I am aware of what you do.' And He said: 'O you who believe, eat from the good things We have provided for you.' Then he mentioned a man who travels for a long time, disheveled and dusty, raising his hands to the sky saying: ‘O Lord, O Lord,’ while his food, drink, and clothing are unlawful, and he is fed with unlawful matter. How can his supplication be accepted?" This hadith is also recorded authentically by Muslim and Tirmidhi. After granting them His provision and guiding them to eat from what is good, Allah clarifies that He has only forbidden them carrion—that which dies by causes other than proper slaughtering, regardless of whether it was strangled, beaten to death, fallen, gored by a beast, or otherwise dead without being ritually slaughtered. The majority specify that the prohibition includes dead sea creatures as well, based on the verse in Al-Ma'idah (5:96) that permits the catch of the sea and its food as lawful provision, coupled with authentic hadith indicating that sea water is pure and its dead creatures are permitted. As for milk and eggs from dead animals, the Shafi‘i school and others consider them impure because they are integral parts of the carcass, though Malik holds that while pure, they become impure if in contact with the carcass. There is some disagreement about the impurity of the smell from carrion, though the majority regard it as impure. Reports mention that the Companions ate some cheese from non-Muslims and that a slight impurity mixed with large amounts of pure liquid is overlooked by the scholars. Moreover, it is forbidden to consume the flesh of swine, whether slaughtered properly or having died naturally, extending also to its fat, since it falls under the ruling of pork by preference or by analogy. Allah forbids eating what is slaughtered in the name of other than Him, such as the offerings to idols and other pre-Islamic pagan practices. Al-Qurtubi relates that Al-Hasan Al-Basri was asked about a woman who slaughtered an animal for a pagan idol celebration and ruled it unlawful. Aisha was also asked about food sacrificed by non-Muslims at their festivals and indicated Muslims should not eat what was slaughtered for that day but may eat from their trees' fruits. Then Allah allows consumption of these forbidden items in cases of genuine necessity and need, when other foods are unavailable, as stated: "But whoever is forced—neither desiring it nor transgressing its limits—there is no sin upon him. Indeed, Allah is Forgiving and Merciful." This means if one is compelled to eat carrion in a situation of dire need without intentional wrongdoing or defiance, it is excused. Mujahid explained that the necessity must be genuine, such as cutting off the path, leaving the righteous community, or being in a sinful situation, but those who do so deliberately have no permission even in need. Said ibn Jubayr and Muqatil bin Hayyan consider the 'not desiring' to mean not deliberately seeking to eat the forbidden out of lust, nor preparing it for delicacy—only consuming the minimal needed to survive. Ibn Abbas interpreted that one should not fully satisfy oneself, and the conditions of not transgressing in consumption were stressed by various scholars. Al-Qurtubi adds that when someone finds both carrion and lawful food without certain harm, they should prefer the lawful food. He then cites a hadith of a man during famine who ate a stalk of grain, had his owner beat him, but the Prophet ﷺ told the owner he had done nothing wrong since he was hungry and unknowing, and ordered the owner to return the man’s garment and feed him. Muqatil bin Hayyan explained that the phrase "there is no sin upon him" in the verse applies to eating from necessity, and it is related that the amount one may consume under necessity should not exceed three bites. Said ibn Jubayr remarked that Allah is forgiving for eating from the forbidden during necessity and merciful for having allowed it in such extremity. Waki‘ narrated from Al-A‘mash and Masruq that whoever is compelled but refrains from eating or drinking and then dies will enter the Fire. This indicates that eating carrion under compulsion is a binding obligation, not a mere concession, comparable to the permitted breaking of fast for the sick in Ramadan and similar cases. In summary, this aya teaches the command to eat from the lawful good provisions of Allah with gratitude, forbids carrion, pork, and what is slaughtered for others than Allah, but in cases of genuine necessity permits eating the otherwise forbidden without sin provided one does not desire it or transgress limits. Furthermore, reliance on authoritative traditions and the explanations of early scholars clarifies these rulings for the believer’s proper practice.

• ✓ Majma al-Bayan fi Tafsir al-Qur'an on 5:5

  Shia

  Majma al-Bayan fi Tafsir al-Qur'an · 5:5

  This verse clarifies what is permissible concerning food and marriage, completing what was previously discussed. It begins: “Today, lawful for you are all good things” — previously explained — which implies the permissibility of all wholesome foods except those explicitly prohibited by evidence. “...and the food of those who were given the Scripture is lawful for you” — Regarding what "food" here specifically refers to, there is disagreement. The majority of commentators and jurists say it means the slaughtered animals of the People of the Book. A group of our companions concur with this. Among them, some specify it means the slaughtered flesh of those who received the Torah and Gospel, those who follow their religion, according to Ibn Abbas, Al-Hasan, Ikrimah, Sa'id ibn al-Musayyib, Al-Sha'bi, 'Ata, and Qatadah. They permit the meat of the Christians, specifically from Banu Taghlib. Others say it applies only to those who were given the Torah and the Gospel or are their descendants, excluding those who merely convert to their religion from other peoples; their slaughtered meat is not permitted, a view attributed to Al-Rabi' from Al-Shafi'i. They forbid the meat of the Christian Banu Taghlib, a statement reported from Ali (peace be upon him) and Sa'id ibn Jubayr. Another group understands “the food of those given the Scripture” to include their slaughtered animals and other foodstuffs, as stated by Abu al-Darda', Ibn Abbas, Ibrahim, Qatadah, Al-Suddi, Al-Dhahhak, Mujahid, and endorsed by Al-Tabari, Al-Jubay'i, Al-Balkhi, and others. Some interpret it narrowly as referring only to grains and items not requiring ritual slaughter, as narrated from Abu Abdullah (peace be upon him), and supported by some Zaydi sect groups; thus, their slaughtered meat remains prohibited. “...and your food is lawful for them” means it is permissible to feed them your food. “...and chaste women from among the believers” means lawful marriage bonds are established with chaste, virtuous believing women, as stated by Al-Hasan, Al-Sha'bi, and Ibrahim. Others say it means free (non-slave) women, a view held by Mujahid and preferred by Abu Ali. According to this, slave women are not permitted for permanent marriage when free women are available. “...and chaste women from those who were given the Scripture before you” refers to Jews and Christians. There is disagreement about their status: some say they mean chaste free women, or war captives as slaves, or protected dhimmis; this is reported from Mujahid, Al-Hasan, and Al-Sha'bi among others. Others say they mean free women, whether dhimmis or captives. Our companions argue that permanent marriage with Christian women is not lawful, citing the prohibition against marrying polytheistic women until they believe, the prohibition against holding free women from disbelievers in marriage bonds, and interpret “chaste women from those given the Scripture” as those among them who converted to Islam, while “chaste women among the believers” refers to those born into Islam. This explanation addresses the concern of some who were reluctant to marry women who converted from disbelief; Allah clarifies there is no harm in this, which is why they are mentioned separately. Abu al-Qasim Al-Balkhi reports this view. They also say it may specifically refer to temporary marriage (mut'ah) and slave concubinage, permissible according to our teachings, though Abu al-Jarud reports Abu Ja'far (peace be upon him) said this was abrogated by the verses forbidding marriage to polytheists and the preclusion of permanent marriage to disbelievers. “...When you have given them their due compensation” means when you give them their bridal payment, a reward or price for the enjoyment of them, as explained by Ibn Abbas and others. “...who are chaste, not committing fornication” means they are modest women who do not engage in immoral acts, serving as a circumstantial description. “...nor taking them as secret lovers” means not having a special relationship with one woman unfaithfully, taking her as a close friend for sinful purposes. The meanings of chastity, fornication, and secret lovers were explained earlier in Surat An-Nisa. “Whoever disbelieves in faith” means whoever denies that which Allah commands belief in and confirmation of — the Oneness of God, His justice, and the Prophethood of His Messenger (peace be upon him and his family). “Their deeds are worthless” — their deeds hold no value. This means that those deeds which they considered as acts of worship to Allah yield no reward. “And they are among the losers in the Hereafter” — doomed to failure. Some say “whoever disbelieves in faith” refers to the People of the Book who refuse to accept faith. Thus, “their deeds are worthless” implies that although these disbelievers perform deeds appearing outwardly as good, because of their disbelief, these deeds do not merit reward. Therefore, their deeds are described as nullified, precisely in meaning.