The Quran said:
The aforesaid verse carries few injunctions for the best of human health and welfare and glad tiding about perfection of the religion Islam. God willing I shall write down its brief exegesis so that the reader may comprehend the implication of the revelation.
Allah has forbidden the believers to eat the following:
- The meat of the cattle that has died on his own. Imam Rhazes said, "When an animal dies of a natural cause the blood is blocked up in its veins and arteries. It gets badly wretched and rotten. Eating its flesh is very much harmful."
- The Blood. The Arab in the ignorance age used to roast the intestines filled with blood and ate it. Allah forbade the believers to use the blood poured forth from the animal in the process of slaying.
Now it has been established through modern research that the blood in the veins and arteries etc carries nutrient material to the tissue cells and brings back waste of tissue metabolism which includes blood urea. These waste products are very harmful to the body and are removed from the blood when it passes through kidney. There is no denial to the kidney's function, if they fail, the body fails. These waste products are thrown out of the body as a water solution we call urine. The urea being part of the blood, Hanafi jurisprudence considers blood as impure (najis).
Further blood carries organism responsible for various diseases. These organisms circulate in the blood without the body manifesting any symptoms of the disease, a condition called sub-clinical infection. The meat of unslayed animals contains much blood. If it is consumed, there is a potential danger of contracting diseases produced through the organisms in the blood. It is also agreed that consuming of blood is destructive of the pure human nature. Allah (God), therefore, not only prohibited the consumption of blood but also order us to slaughter the animal in a way to achieve the maximum extraction of the blood from the body.
Now the progress of our medical science made us to learn the wisdom in the prohibition of eating all those cattle's who have died either by strangling or stunning, or falling from a height, or killed by the goring of the horns, or partly eaten by the wild beast, in all these cases the blood blocks up in the veins and arteries etc. There is only one exception to the above rule that if you make it pure by slaying it in the name of Allah before its soul departs its body. That can be done only, if we find some movement in the dying animal.