Al-Isra 17:82

<h2>The Qur'an is a Cure and a Mercy</h2><p>Allah tells us that His Book, which He has revealed to His Messenger Muhammad ﷺ, the Qur'an to which falsehood cannot come, from before it or behind it, (it is) sent down by the All-Wise, Worthy of all praise, is a cure and a mercy for the believers, meaning that it takes away whatever is in their hearts of doubt, hypocrisy, Shirk, confusion and inclination towards falsehood. The Qur'an cures all of that. It is also a mercy through which one attains faith and wisdom and seeks goodness. This is only for those who believe in it and accept it as truthful, it is a cure and a mercy only for such people. As for the disbeliever who is wronging himself by his disbelief, when he hears the Qur'an, it only makes him further from the truth and increases him in his disbelief. The problem lies with the disbeliever himself, not with the Qur'an, as Allah says:</p><p>قُلْ هُوَ لِلَّذِينَ ءَامَنُواْ هُدًى وَشِفَآءٌ وَالَّذِينَ لاَ يُؤْمِنُونَ فِى ءَاذَانِهِمْ وَقْرٌ وَهُوَ عَلَيْهِمْ عَمًى أُوْلَـئِكَ يُنَادَوْنَ مِن مَّكَانٍ بَعِيدٍ</p><p>(Say: "It is for those who believe, a guide and a cure. And as for those who disbelieve, …

And We reveal of the Qur'an that which is a healing and a mercy for believers though it increase the evil-doers in naught save ruin.

We send down (stage by stage) in the Qur'an that which is a healing and a mercy to those who believe: to the unjust it causes nothing but loss after loss.

And We send down from the Quran that which is a healing and a mercy to those who believe (in Islamic Monotheism and act on it), and it increases the Zalimun (polytheists and wrong-doers) nothing but loss.

We send down in the Quran healing and mercy for the believers, but it increases the wrongdoers only in loss.