المعنى الاصطلاحي :

Sources of Islamic legislation whose validity are not debated by the scholars of the Muslim Ummah. They are the Qur’an, the Sunnah, "ijmā‘" (consensus), and "qiyās" (analogy).

الشرح المختصر :

"Adillah muttafaq ‘alayha" (agreed-upon proofs): The scholars of Ahl-us-Sunnah agree that the sources upon which the Islamic Shariah is founded and from which legal rulings are deduced are four: the Qur’an, the Sunnah, "ijmā‘" (consensus), and "qiyās" (analogy). They all go back to two sources: the Qur’an and the Sunnah."Ijmā‘" and "qiyās" rely on the Qur’an and the Sunnah in establishing their proofs, while "qiyās" is an agreed-upon source as a whole.