The Qur’aan is a Cure
Allaah Jala Jallalahu said:
( ولو جعلناه قرآنا أعجميا لقالوا لولا فصلت آياته أأعجمي وعربي قل هو للذين آمنوا هدى وشفاء) [ فصلت:44]
《And if We had sent this as a Qur’aan in a foreign language other than Arabic, they would have said: “Why are not its Verses explained in detail (in our language)? What! (A Book) not in Arabic and (the Messenger) an Arab?” Say: “It is for those who believe, a guide and a healing.》[Fussilat : 44]
Al-Imam Ibn al-Qayyim -Rahimahullaah- said:
‘The Qur’aan is the complete cure for all illnesses of the heart, the body and the illnesses of the Duniya and Hereafter.
Not everyone qualifies and is successful to be able to seek a cure by the Qur’aan.
If the sick person uses the Qur’aan properly for a cure by applying it to his disease with truthfulness, Eemaan, complete acceptance, with certainty of belief and fulfilling its requirements then the disease cannot ever resist it.
So how can illnesses have any strength against the Speech of the Lord of the heavens and earth. This speech if it was revealed to a mountain, it would cause it to crack and crumble, or if it was revealed to the earth it would cause it to split apart. There is no illness from the illnesses of the hearts and bodies except that there is in the Qur’aan, a way which indicates to its medication, and a means and protection from the illness for the one whom Allaah provides an understanding of His Book.’
[Zaad al-Ma’ad 4/352]