Urf

ʿUrf (Arabic: العرف‎‎) is an Arabic Islamic term referring to the custom, or 'knowledge', of a given society. To be recognized in an Islamic society, ʿurf must be compatible with the Sharia law. When applied, it can lead to the deprecation or inoperability of a certain aspect of fiqh فقه (Islamic jurisprudence).

ʿUrf is a source of rulings where there are not explicit primary texts of the Qur'an and Sunnah specifying the ruling. ʿUrf can also specify something generally established in the primary texts.

In some countries such as Egypt, marriage, the ʿurfi way, means to get married without official papers issued by the state (زواج عرفي Zawag ʿUrfi). The validity of this type of marriage is still under debate. see: common law marriage.

The term ʿurf, meaning "to know", refers to the customs and practices of a given society. Although this was not formally included in Islamic law, the Sharia recognizes customs that prevailed at the time of Muhammad but were not abrogated by the Qur'an or the tradition (called "Divine silence"). Practices later innovated are also justified, since Islamic tradition says what the people, in general, consider good is also considered as such by Allah (see God in Islam). According to some sources, ʿurf holds as much authority as 'ijma (consensus), and more than qiyas (legal reasoning by analogy). ʿUrf is the Islamic equivalent of "common law".

ʿUrf was first recognized by Abū Yūsuf (d. 182/798), an early leader of the Ḥanafī school. But it was considered part of the sunnah, and not as formal source. Later al-Sarak̲h̲sī (d. 483/1090), opposed it, holding that custom cannot prevail over a written text.

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