Being presumptuous toward the Quran and the Sunnah is a dangerous venture, especially when it comes from scholars, for the depths of the Holy Quran are unfathomable — it is not the speech of human beings. It remains a field for lifelong research and discovery of its miraculous nature, bound to no particular time or place. As the poet says:
All knowledge lies within the Quran, yet
The minds of men fall short of grasping it.
The same applies to the Prophetic Sunnah, for the Messenger, peace be upon him, does not speak from desire — it is but revelation inspired.
Yes, we have the right to investigate the source of a hadith, but once it is established as an authentic hadith, a believer may not reject it simply because his limited mind cannot comprehend it. The Quran is a red line, and so is the Sunnah.
On this basis, the claim made by some scholars that not all of the Quran constitutes a healing recitation — citing the words of God Almighty: "And We send down of the Quran that which is a healing and a mercy to the believers" (verse 82 of Surah Al-Isra) — amounts to presumptuousness toward God.
Their argument is that the Arabic particle "min" (من) here is partitive, meaning "some" of the Quran. The correct view, however, is that "min" here is explanatory, referring to the genus of the Quran as a whole, as Ibn al-Qayyim, may God have mercy on him, states in his book "Zad al-Ma'ad."
Furthermore, the fact that the Messenger, peace be upon him, would instruct his companions to treat every sick person with Al-Fatihah, Ayat Al-Kursi, the last two verses of Surah Al-Baqarah, Surah Al-Ikhlas, and the two protective surahs (Al-Mu'awwidhatan) is because these verses are universal and a cure for all ailments — not because the other verses of the Quran contain no healing.
Beyond this, one should understand that, just as modern medicine has general practice and medical specialisation, so too does Quranic and Sunnah-based healing — without drawing a direct comparison — encompass both general ailments and specific ones.
For general ailments, the healing recitation is found in the verses the Messenger identified, and each of us is able to recite them for ourselves. As for specific ailments, the rest of the Quranic surahs apply, and these require someone with specialised understanding of the Quran and Sunnah.
By way of example, patients with diabetes, high blood pressure, and similar conditions — where the cause is not spiritual — may, in addition to following their doctor's guidance, seek Sharia-compliant healing recitation, including the general healing verses already mentioned, supplemented by other verses such as the words of God Almighty: "For every announcement there is a term, and you will come to know" (verse 67 of Surah Al-An'am).
What we have mentioned is an example, and you may apply it to all ailments that can be treated through the Quran, for there is nothing in the Quran that is not a source of healing — yet most people do not know.