ما المقصود بالمفصل، ومن أين تبدأ سوره؟

The Mufassal (Detailed) section of the Qur’an begins from Surat Qaf to the end of the Qur’an. The proof for this is what Abu Dawud narrated from Aws bin Hudhayfah regarding the division of the Qur'an into hizb (parts), where he said: "And he made the Mufassal section a hizb by itself."

The Mufassal begins with Surat Qaf and ends with Surat An-Nas. It was named Mufassal due to the frequent separation between its surahs by the Basmalah (Bismillahirrahmanirrahim). The Mufassal comprises long surahs (from Qaf to An-Naba'), medium surahs (from An-Naba' to Ad-Duha), and short surahs (from Ad-Duha to the end of the Qur'an).