Tafsir bi-l-Ma'thur and bi-l-Ra'y, Two Ways of Filling the Same Gap

Classical scholars of tafsir sorted their own tradition into two broad methods, and the distinction still organizes how the genre is taught. Tafsir bi-l-ma'thur, exegesis by transmission, explains a Quranic verse using material already inside the tradition: another verse of the Quran, a saying of Muhammad, or a report from a companion who had heard the verse's occasion of revelation firsthand. Al-Tabari's tenth century commentary is the model of this method at its most expansive, gathering every chain of transmission he could find for a given verse and setting them side by side, often without choosing between them, so a reader sees the range of early opinion rather than one settled answer. Tafsir bi-l-ra'y, exegesis by considered opinion, reasons instead from Arabic grammar, legal principle and theological argument once transmitted material is exhausted or silent, a method scholars across the classical schools debated the limits of rather than rejected outright, since applying the Quran's general commands to particular new cases was understood to require some exercise of reason. Ibn Kathir's fourteenth century commentary, still one of the most widely read Sunni tafsirs, narrowed al-Tabari's expansive transmission into a tighter, more doctrinally consistent selection, explicitly stating the principle that the Quran is best explained by the Quran itself, then by hadith, and only then by the companions' own testimony. Neither approach existed in pure form: a transmission-based commentator still chose which reports to include, and a rationalist exegete still worked inside inherited language and precedent. Modern reformist tafsir keeps testing how much room bi-l-ra'y should have against that inheritance.