The great Imam Al-Qarafi said in this book: "Rules are not fully covered in Usul al-Fiqh; rather, there are many rules of Sharia among the imams of fatwa and jurists that are not found in Usul al-Fiqh books at all. This is what prompted me to write this book, to document those rules to the best of my ability."

Thus, his methodology in this book was to establish this discipline by relying on two complementary pillars: comprehensive rules and Sharia objectives. To complete the desired benefit from this book, he appended to it (Idrar Al-Shurooq ala Anwar Al-Furooq) by Imam Abu Al-Qasim Ibn Al-Shat, who revised Al-Qarafi's book and added to it, resulting in a comprehensive and enjoyable book.