What are the primary sources of Sharia law and how do they interact (Qur'an, Sunnah, ijma, qiyas)?
Executive summary
Sharia’s classical toolbox rests on four recognised sources: the Qur’an and Sunnah as primary scriptures, with ijma (scholarly consensus) and qiyas (analogical reasoning) as secondary methods used when scripture is silent or general; this framework was systematised by medieval jurists and remains the baseline for Sunni fiqh (Islamic jurisprudence) [1] [2] [3]. How those sources are applied—whether strict textual priority, expansive analogy, or appeals to communal objectives—varies by school, by Sunni versus Shia legal theory, and by modern state practices, producing real-world legal diversity and ongoing debate [1] [4] [5].
1. The Qur’an: the textual foundation and limiting horizon
The Qur’an is universally treated as the first and supreme source of Sharia: it supplies commandments, principles and the core legal text from which other rulings must not contradict, and classical manuals emphasise that all subsequent reasoning must be grounded in the Qur’an’s wording and purposes [3] [6] [1].
2. The Sunnah: the Prophet’s practice as interpreter and supplement
The Sunnah—embodied primarily in hadith collections of the Prophet’s sayings, actions and tacit approvals—serves both to clarify general Qur’anic commands and to supply rulings on matters the Qur’an treats only broadly; jurists therefore treat authentic Sunnah as the second primary source and as essential to turning Qur’anic principles into concrete law [1] [7] [8].
3. Ijma (consensus): communal closure when texts are silent
When the Qur’an and Sunnah do not resolve a question, Sunni tradition turns to ijma, the consensus of qualified scholars or of the community of jurists, as a binding secondary source that can stabilise law and close disputes—though historians and modern scholars note that what counts as “consensus” has itself been contested and constructed over time [2] [1] [9].
4. Qiyas (analogy): extending precedent by shared cause
Qiyas is the classical method of analogical deduction: jurists identify the effective cause (ʿillah) in a Qur’anic or Prophetic ruling and extend the same ruling to new cases that share that cause; schools such as the Hanafi elevated qiyas’ role to address novel problems, while others restrained its scope, and Shiʿi frameworks often substitute reason (ʿaql) or different tools for formal qiyas [2] [4] [10].
5. Interaction and hierarchy in practice: texts first, methods to fill gaps
Traditional Sunni doctrine places the Qur’an and authenticated Sunnah at the top; ijma can then confirm or lock in interpretations, and qiyas operates as a principled stopgap for new questions—together these form a ladder jurists climb when the primary texts are silent, ambiguous, or general, with methodology (usul al-fiqh) formalised by figures such as al-Shafiʿi [1] [2].
6. Divergences, auxiliary tools and modern pressures
Beyond the fourfold schema, jurists historically used ijtihad (independent reasoning), maslaha or maqasid (considerations of public interest and objectives), and local custom (ʿurf); modern debates press these auxiliary principles either into service as normative sources in their own right or as corrective lenses—an approach critics say can liberalise Sharia while opponents warn it risks departing from scripture [1] [9] [11].
7. From juridical theory to state law: fatwas, courts and constitutions
Sharia’s sources inform fatwas and judicial rulings but interact differently with modern institutions: in some states Sharia is “a source” among many in constitutions, in others it is the primary law; fatwas remain advisory in Sunni settings but state courts and legislatures often decide which sources or schools govern practice, producing variation in family, criminal and financial law across countries [5] [12] [11].
Conclusion
The classical quartet—Qur’an, Sunnah, ijma, qiyas—provides an interconnected methodology where scripture speaks first and juristic techniques supply interpretation and application; the balance among them, however, is historically contingent and politically charged, with competing schools, Shia alternatives, and modern state systems all reshaping how Sharia’s sources operate in practice [1] [4] [5].