This explanation in the form of a question and answer
Q: Science tells us that whatever one eats has an effect on ones behaviour. Why does then Islam allow Muslims to eat non-vegetarian food, since eating of animals could make a person violent?
A: 1. Only eating of herbivorous animals is allowed by Islam. I agree that, what a person eats has an effect on his behaviour. This is one of the reasons why Islam prohibits the eating of carnivorous animals like lions, tigers, leopards, etc. who are violent and ferocious. The consumption of the meat of such animals would probably make a person violent and ferocious. Islam only allows the eating of herbivorous animals like goats, cattle, sheep, etc. that are peaceful and docile. We Muslims eat peaceful and docile animals because we are peace loving and non-violent people.
2. The Quran says Prophet prohibits what is bad
The Quran says: The Prophet commands them what is just and prohibits what is evil. He allows them as lawful what is good (and pure) and prohibits them what is bad (and impure), [Al-Araf 7: 157]
So take what the Messenger assigns to you and deny yourselves that which he withholds from you. [Al-Hashr 59: 7]
For a Muslim, the Prophets statement is sufficient to convince him that Allah does not wish humans to eat some kinds of meat while allowing some other kinds.
3. Hadith prohibiting eating of carnivorous animals
According to various authentic Ahaadith narrated in Sahih Bukhari and Sahih Muslim including hadith narrated by Ibn Abbas in Sahih Muslim, Book of hunting and slaughter, Hadith No. 4752 and Sunan Ibn-i-Majah chapter 13 Hadith no. 3232 to 3234, the Holy Prophet (Pbuh) prohibited the eating of:
(I) Wild animals with canine teeth, i.e. meat eating carnivorous animals. These are animals belonging to the cat families such as lions, tigers, cats, dogs, wolfs, hyenas, etc.
(Ii) Certain rodents like mice, rats, rabbits with claws, etc.
(Iii) Certain reptiles like snakes, alligators, etc.
(Iv) Birds of prey with talons or claws, like vultures, eagle, crows, owl, etc.
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