The author begins with 4 principal proof families used in the study of Shariah rulings:
• The Book of Allah: Quranic verses connected to rulings.
• The Sunnah of the Messenger ﷺ: transmitted Prophetic guidance connected to rulings.
• Ijma: agreement of qualified jurists, under its proper conditions, on a Shariah ruling.
• Qiyas: extending a source-established ruling from an original case to a new case when the same legally relevant reason is found in both.
These are brief first definitions only. Their evidence, conditions and detailed use are taught in later assigned levels.