Anyone who seeks to understand Islam must have recourse to the Koran. The Koran, according to Muslim belief, is the Word of God, the Revelation of His divinity and His command to men; it is the basis of the Islamic religion, a basis which has remained unaltered during the course of history, even if it is constantly experienced and interpreted anew. But the Koran itself is a book which is difficult of access. This is for external and internal reasons: external because in the present arrangement of the texts of the Revelation it is not possible to work out the original chronological sequence; internal because without a knowledge of the historical context it is not really possible to understand either the message in its entirety or many of the details of, and allusions to, its environment. These associations, moreover, have only been preserved for us by the manifold facets and reflections of religious tradition (Source: Islam: A Historical Introduction).