Allah commands His believing servants to eat from the pure things that He has created for them and to thank Him for it, if they are truly His servants. Eating from pure sources is a cause for the acceptance of supplications and acts of worship, just as eating from impure sources prevents the acceptance of supplications and acts of worship, as mentioned in a Hadith recorded by Imam Ahmad, that Abu Hurayrah said that Allah's Messenger said:
«أَيُّهَا النَّاسُ إِنَّ اللهَ طَيِّبٌ، لَا يَقْبَلُ إِلَّا طَيِّـبًا، وَإنَّ اللهَ أَمَرَ الْمُؤْمِنِينَ بِمَا أَمَرَ بِهِ الْمُرْسَلِينَ، فَقَالَ:
﴿يأَيُّهَا الرُّسُلُ كُلُواْ مِنَ الطَّيِّبَـتِ وَاعْمَلُواْ صَـلِحاً إِنِّى بِمَا تَعْمَلُونَ عَلِيمٌ ﴾
﴿يـأَيُّهَا الَّذِينَ ءَامَنُواْ كُلُواْ مِن طَيِّبَاتِ مَا رَزَقْنَـكُمْ﴾
ثُمَّ ذَكَرَ الرَّجُلَ يُطِيلُ السَّفَرَ أَشْعَثَ أَغْبَرَ يَمُدُّ يَدَيْهِ إِلَى السَّمَاءِ: يَا رَبِّ يَا رَبِّ، وَمَطْعَمُهُ حَرَامٌ، وَمَشْرَبُهُ حَرَامٌ، وَملْبَسُهُ حَرَامٌ، وَغُذِّيَ بالْحَرَامِ فَأَنَّى يُسْتَجَابُ لِذلِكَ؟»
(O people! Allah is Tayyib (Pure and Good) and only accepts that which is Tayyib. Allah has indeed commanded the believers with what He has commanded the Messengers, for He said: (O (you) Messengers! Eat of the Tayyibat and do righteous deeds. Verily, I am well-acquainted with what you do) (23:51), and: (O you who believe! Eat of the lawful things that We have provided you with) He then mentioned a man, (who is engaged in a long journey, whose hair is untidy and who is covered in dust, he raises his hands to the sky, and says, `O Lord! O Lord!' Yet, his food is from the unlawful, his drink is from the unlawful, his clothes are from the unlawful, and he was nourished by the unlawful, so how can it (his supplication) be accepted'') It was also recorded by Muslim and At-Tirmidhi
After Allah mentioned how He has blessed His creatures by providing them with provisions, and after commanding them to eat from the pure things that He has provided them, He then stated that He has not prohibited anything for them, except dead animals. Dead animals are those that die before being slaughtered; whether they die by strangling, a violent blow, a headlong fall, the goring of horns or by being partly eaten by a wild animal. Dead animals of the sea are excluded from this ruling, as is explained later, Allah willing, as Allah said:
﴿أُحِلَّ لَكُمْ صَيْدُ الْبَحْرِ وَطَعَامُهُ﴾
(Lawful to you is (the pursuit of) watergame and its use for food) (5:96), and because of the Hadith about the whale recorded in the Sahih. The Musnad, Al-Muwatta' and the Sunan recorded the Prophet saying about the sea:
«هُوَ الطَّهُورُ مَاؤُهُ والْحِلُّ مَيْتَتُه»
(Its water is pure and its dead are permissible.)
Ash-Shafi`i, Ahmad, Ibn Majah, and Ad-Daraqutni reported that Ibn `Umar said that the Prophet said:
«أُحِلَّ لَنَا مَيْتتَانِ وَدَمَانِ،السَّمَكُ وَالْجَرَادُ وَالْكَبِدُ وَالطِّحَال»
(We have been allowed two dead things and two bloody things: fish and locusts; and liver and spleen).
We will mention this subject again in Surat Al-Ma'idah (chapter 5 in the Qur'an), In sha' Allah (if Allah wills).
Issue: According to Ash-Shafi`i and other scholars, milk and eggs that are inside dead unslaughtered animals are not pure, because they are part of the dead animal. In one narration from him, Malik said that they are pure themselves, but become impure because of their location. Similarly, there is a difference of opinion over the cheeses (made with the milk) of dead animals. The popular view of the scholars is that it is impure, although they mentioned the fact that the Companions ate from the cheeses made by the Magians (fire worshippers). Hence, Al-Qurtubi commented: "Since only a small part of the dead animal is mixed with it, then it is permissible, because a minute amount of impurity does not matter if it is mixed with a large amount of liquid.'' Ibn Majah reported that Salman said that Allah's Messenger was asked about butter, cheese and fur. He said:
«الْحَلَالُ مَا أَحَلَّ اللهُ فِي كِتَابِهِ، وَالْحَرَامُ مَا حَرَّمَ اللهُ فِي كِتَابِهِ، وَمَا سَكَتَ عَنْهُ فَهُوَ مِمَّا عَفَا عَنْه»
(The allowed is what Allah has allowed in His Book and the prohibited is what Allah has prohibited in His Book. What He has not mentioned is a part of what He has pardoned.)
Allah has prohibited eating the meat of swine, whether slaughtered or not, and this includes its fat, either because it is implied, or because the term Lahm includes that, or by analogy. Similarly prohibited are offerings to other than Allah, that is what was slaughtered in a name other than His, be it for monuments, idols, divination, or the other practices of the time of Jahiliyyah. Al-Qurtubi mentioned that `A'ishah was asked about what non-Muslims slaughter for their feasts and then offer some of it as gifts for Muslims. She said, "Do not eat from what has been slaughtered for that day, (or feast) but eat from their vegetables.''