Al-Risala is the best known work of al-Shafi'i, noted especially for its clear Islamic jurisprudence. In this work, al-Shafi'i is said to have outlined four sources of Islamic law, though this division based on four has been attributed to later commentators on the work rather than to Shafi'i himself.
Sources of law in Al-Risala
The primary sources of law attributed to Shafi'is book are the Qur'an and the prophetic tradition. Most Muslim commentators have also referred to Shafi'is sections on consensus and analogical reason as comprising legal sources.
On the question of consensus, Shafi'i obligated affirmation of all living Muslims - both the learned and the laymen - in order to declare a true consensus. Later followers of his school considered this to be practically impossible, and thus expanded upon the definition.
- McNeill, William H., and Marilyn Robinson Waldman. The Islamic World. University of Chicago Press, 1973.
- Islamic Jurisprudence: Shafi'i's Risala, trans. by Majid Khadduri, Baltimore: Johns Hopkins University Press, 1961.
- "Does Shafi'i Have a Theory of 'Four Sources' of Law?, taken from the PhD dissertation of Joseph E. Lowry, The Legal-Theoretical Content of the Risala of Muhammad B. Idris al-Shafi'i, University of Pennsylvania, 1999.
- Khadduri, Introduction to Shafi'i's Risala, pg.33
- Khadduri, pg. 38-39