What is the miraculous aspect of the Holy Quran, according to the Sunnis and the Community (Ahl al-Sunnah wal-Jama'ah)? And is the statement that only the long surahs are miraculous considered disbelief (kufr)? And is it better to avoid delving into this topic?

The scholars have not differentiated between short and long surahs (chapters) concerning their miraculous nature. There has been a difference of opinion regarding the miraculous measure of the Qur’an, with several views. The most preponderant view is that the miraculous nature pertains to both small and large portions of the Qur’an. The majority of scholars hold that the miraculous nature is related to a complete surah, whether long or short, and that the shortest surah (three verses) is miraculous. A distinction must be made between what constituted the challenge—which was a complete surah—and the measure that indicates the Qur’an is the word of Allah, which can be understood from a verse, part of a verse, or even a word. One who says that the miraculous nature is only found in a long surah does not commit disbelief, though this view is invalid, yet it does not contradict the clear text of the Qur’an.