Scholars have differed over the reason it is called the Mother of the Book. One view holds that, because it is written before all the other surahs, it leads them by its precedence. […] (1) Accordingly, the entire Book returns to the meanings found in it; it functions as the very root of the Scripture, just as Mecca has been called “the Mother of Cities” because the other lands were spread out from beneath it.

Another explanation is that its primacy stems from the fact that it is definitive and has never been subject to abrogation, in harmony with His words: “Among it are verses that are clear and decisive—they are the foundation of the Book” (Āl ʿImrān 3:7).

Other interpretations have also been suggested, and Allah knows best.

The third designation is Umm al-Qurʾān (Mother of the Qurʾān), a name attested in many hadiths. Among them is the report of Abū Hurayrah in which the Prophet ﷺ said, “Every prayer in which the Mother of the Qurʾān is not recited is defective,” recorded by Muslim (2). Muslim also transmitted the hadith of ʿUbādah in which the Prophet ﷺ declared, “There is no prayer for the one who does not recite the Mother of the Qurʾān” (3).

Many scholars have used this title, among them al-Hasan.