ABSTRACT
Islamic law purports to be unchanging and valid throughout the Islamic world. Local custom thus comes in, as one might say, through a side door as a source of law, without being explicitly recognised as such. For medieval Islamic law, especially those segments concerned with economic exchange, this term is particularly felicitous. The notion of "local knowledge" permeates some of its major institutions and is built into its very structure and formulation. Islamic law saw itself as an extension of the word of God, as a system of conduct in matters rituai, social, economic and personal, by adhering to which any individual would ensure himself a favorable outcome on the Day of Judgment. Islamic legal scholars have been producing compendia of religious law since the 9th century.
