The sharia in its classical form differs from Western legal systems because it governs a person’s relationships with their neighbors, the state, God, and their own conscience. It is a comprehensive code of behavior that includes both private and public activities.
Sharia duties are split into obligations to God, like daily prayers, almsgiving, fasting, and pilgrimage, and those to other people. The latter includes offenses such as homicide or assault, which are punishable by retaliation unless the victim opts for compensation instead. Fixed punishments (ḥadd) exist for specific crimes. Starting in the 19th century, most Muslim countries adopted Western criminal codes patterned after French, Swiss, or British systems of justice, although family law (marriage, divorce, inheritance) often are governed by the sharia.
The four root transactions of the sharia are sale, hire, gift, and loan, which apply to pledge, deposit, guarantee, land tenancy, and other transactions. The doctrine of ribā (usury) significantly influences the Islamic law of transactions by precluding any form of interest on a capital loan or investment. As with criminal law, most Muslim countries use financial laws based largely on Western legal models, although instruments of Islamic finance, which are subject to additional requirements under the sharia, are often recognized within these legal frameworks and those of some Western countries.