A: Parts of the Islamic holy book, the 'Hadith' 

The Holy Prophet (peace be on him) said: Cleanliness is half of Faith. Keep your houses and yards tidy. God does not like dirt and cleanses the mouth not trim his nails and untidiness. Brushing the teeth pleases God. He who does his moustache is not one of us. He who goes to sleep while his hands smell of food has only himself to blame if harm comes to him. Every Muslim must have a bath once a week, when he must wash his head and the whole of his body. Do not put up a sick man and a healthy one together. If you hear of the plague keep away from it. If the plague breaks out in the area where you are, do not leave.

Question: How useful is this source to historians studying oriental medicine?

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