1. The person slaughtering the animal must be a Muslim, whether it is a man or a woman. The child of a Muslim who is of distinguishing age, in that he can distinguish good from evil, can also slaughter the animal. However, if a k¡fir, a n¡¥ibi, a kh¡riji or a gh¡li who is considered a k¡fir, such as those who believe in the divinity of Imam ‘Ali (as), slaughters an animal, it will not become lawful for consumption.
2. They should slaughter the animal with a tool made of iron. However, if an iron-tool is not available, the animal can slaughtered using a sharp tool that is able to sever its four pathways, such as a piece of glass or a rock. Obligatory precaution dictates that the situation be such that if the animal is not slaughtered it would die, or another reason necessitates slaughtering the animal.
3. Whilst slaughtering the animal, the front of the animal should face the qiblah. If someone knows that the animal should be slaughtered facing the qiblah, and he intentionally fails to make it face the qiblah, that animal will be unlawful to consume. However if he forgets about it, or does not know about the precept, or mistakes the direction of the qiblah, or does not know the direction of the qiblah, or is unable to make the animal face the qiblah, but is forced to slaughter the animal, then there is no problem in it.
4. When the person wants to slaughter the animal, or places the knife on its throat with the intention of slaughtering it, he should pronounce the name of God. The mere pronouncement of bismill¡h or all¡hu akbar or any similar invocation will suffice. In fact, saying Allah by itself is also sufficient. However, if he invokes the name of God without the intention of slaughtering the animal, the animal will not be §¡hir and neither will its meat be lawful for consumption. Nevertheless, if he forgets to invoke the name of God, there will be no harm in it. The recommended precaution is that whenever he recollects, he should invoke the name of God.
5. The animal should show some movement after being slaughtered, even if it be moving its eyes or tail, or striking its feet against the ground. This ruling applies in the case where there is doubt as to whether the animal is alive or not whilst being slaughtered. Otherwise, there is no need for it. It is also obligatory that a usual amount of blood that is normal and common for that type of animal should drain out of the body.
6. The obligatory precaution is that the head of an animal, other than birds, should not be separated from the body before the spirit has left its body. In fact, this act is also problematic in the case of birds. However, if the head is separated accidentally or owing to the sharpness of the knife, it will not be problematic.
The obligatory precaution is that the spinal marrow which extends from the cervical vertebrae to the tail of the animal, and is commonly known as the [nik¡h in Arabic] marriage, should not be cut intentionally.
7. The obligatory precaution is that the animal be slaughtered from the front of the neck and not the nape of the neck. Similarly, based on obligatory precaution, it is not permissible to insert the knife under the pathways, and then cut them towards the front.