Islamic law, or shari’a, is a series of principles that are interpreted, negotiated, and debated by legal scholars and adapted in the lives of Muslims in order to bring their actions in line with God’s vision for a just and good life. On the everyday level, Islamic law regulates when and how a Muslim prays, what is considered permissible to eat, business transactions, almsgiving, fasting, and so on. For observant Muslims, Islamic law creates the structure, to varying degrees, by which they organize their lives and decisions; shari’a literally means “the way.”
Muslims understand the rules of shari’a to have been sent by God in the text of the Qur’an, but also made manifest in the hadith and sunnah, sayings of and stories about the Prophet Muhammad. Jurisprudence and specific laws—referred to as fiqh, which means “understanding”—are direct interpretations of the shari’a through these texts by Islamic scholars (‘ulama). Historically, various strains of jurisprudence became systematized as separate legal schools among Sunnis (Hanafi, Shafi'i, Maliki and Hanbali) and Shi’a Muslims (Ja'fari), though with significant interpretive diversity even within a single school. Because of the multiplicity of interpretations, there is never ‘one way’ to understand the shari’a, and robust debate and conversation between these schools was a feature of Islamic jurisprudence throughout history.
Islamic law is also a means by which historically and today Muslims organize and regulate society, with implications in business, family, civil, and criminal law. Modern global Islamic banks have arisen in the past few decades in response to a growing demand for financial systems that accommodate Islamic legal principles forbidding usury as well as investment in sectors deemed to be inconsistent with Islamic morals, for example, gambling. Even in countries that do not make reference to Islamic law in their legal codes, marriage and divorce among Muslims involves Islamic legal agreements, often including written contracts, which take place outside of a civil marriage ceremony.
Criminal law constitutes a small portion of fiqh, and includes the punishments most often immediately associated with shari’a outside of the Muslim world. Even among states that point to Islamic law as the source of legislation, many—including Egypt—do so selectively and do not apply corporal punishments in criminal cases.
Jean Michiel Otto, “Introduction: investigating the role of sharia in national law,” Sharia Incorporated: A Comparative Overview of the Legal Systems of Twelve Muslim Countries in Past and Present, ed. Jean Michiel Otto (Leiden: Leiden University Press, 2010), pp. 17-50.