*Islamic dietary laws begin in the Quran, dictated to the Prophet Mohammed by the angel Gabriel around 620 AD. Then there are the Sunnah, the deeds of the Prophet, or the things he recommended or approved; and the hadith, the sayings of the Prophet, relayed through people who knew him. The combination of the Quran with the deeds and sayings of the Prophet Mohammed make up the rules of Islam. There is no centralized Islamic authority, so there are differences of opinion based on the Shariah (religious legislation), varying by region/country or sect.