Complex sentence: After the time of the Prophet, Caliphs (from the Arabic word "Khalifah" which means successor of the Prophet), would rule according to the Law of Islam, which consists of the law found in the Quran and in the narrations from the Prophet.
Split into simpler sentences: After the time of the Prophet, Caliphs (from the Arabic word "Khalifah" which means successor of the Prophet), would rule according to the Law of Islam. The Law found in the Quran and in the narrations from the Prophet.