There is in the Qur'an a healing power that cures obsession, anxiety, and hesitation. It establishes a bond between believers' hearts and God. This bond imparts inner peace to believers as they experience a feeling of security in God's protection. They are happy and satisfied with what they receive from God and contented with their lot in life.
Anxiety, hesitation, and obsession are all terrible to experience. As the Qur'an dispels all these, it is indeed a blessing for true believers.
In the Qur'an we have a cure from greed, envy, and evil thoughts. All these cause sickness of the heart and mind, leading to debility and utter ruin. As the Qur'an cures these, it is a tool of grace bestowed by God on those who truly believe in Him.
The Qur'an also provides a cure from deviant thoughts and feelings. It protects the mind from going far astray, while allowing it complete freedom within its fruitful pursuits. It stops the mind from wasting its energy over what is devoid of use. It lays down for it a sound approach that ensures good and useful results.
The same principle applies to the human body, ensuring that its resources are utilized for what is useful and fruitful, steering human beings away from the suppression of natural desires or indulgence without restraint.
Thus it ensures a healthy body. In this again we see that the Qur'an is a means of God's grace that is bestowed on believers.
There is also in the Qur'an a cure for social ailments that weaken the structure of society and destroy its peace and security. Under the social system established by the Qur'an, society enjoys perfect justice in peace and security. This is again a further aspect of grace bestowed through the Qur'an.
However, the Qur'an [only adds to the ruin of the evildoers] (Al-Israa' 17:82). They make no use of the cure it provides or the blessings it brings about. They look with dismay at the believers as they feel proud to be among the followers of the Qur'an.
In their stubborn arrogance, the evildoers persist with their corrupt and unjust methods. Yet in this life, they are defeated by the followers of the Qur'an, which makes them losers. In the life to come, they suffer for their arrogant disbelief and tyranny, and thus they lose again. Hence the Qur'an adds to their ruin.
When man is left to his own devices, without the cure and blessing of the Qur'an, and without consistent restraint of his whims and desires, he moves between two extremes: when he enjoys good fortune, he is arrogant and ungrateful, and when he experiences hardship he is given to despair.