Commentary
Previous verses described how astray the disbelievers and polytheists had gone and what punishments had become due against them in the Hereafter.
Shown to them in the first two verses was the way out of their living in error and also the source through which they would find deliverance from the punishment of the Hereafter. And that source is Qur'an, the Book of Allah, and His Messenger, Muhammad al-Mustafa ﷺ .
Both are great blessings for humanity, far superior to the entire blessings of the heavens and the earth. Following the injunctions of the Qur'an and the way of the Holy Prophet ﷺ go on to make human beings human in the real sense - and when this human person becomes the perfect man in the real sense, the whole world corrects and reorders itself like a paradise on earth.
The first (57) of the five verses cited above mentions four attributes of the Holy Qur'an:
1\. ADVICE as in مَّوْعِظَةٌ مِّن رَّبِّكُمْ (an advice from your Lord).
The real meaning of the word: مَّوْعِظَةٌ (maw` izah) and: موعظ ، (wa` z) is to delineate such things as would make one's heart soft and receptive. As a result, it would incline towards Allah Ta` ala. The barrier of heedlessness acquired from excessive indulgence in worldly life will stand removed. Ultimately, this advice would result in the flowering of a personal concern for what would happen in Akhirah, the life ahead. The Holy Qur'an, from the beginning to the end, is an eloquent preacher of this very good counsel. See anywhere, you will find promise with warning, reward with punishment, and prosperity and success in Dunya and Akhirah with a corresponding fate due to error and straying. Appearing recurrently in varying shades and blending, it generates a powerful appeal which has the ability to make a heart stone-hard turn soft and pliable like water all ready to absorb the message. Of course, on top of everything, there is the miraculous diction of the Holy Qur'an that, by itself, has a class of its own in the matter of reversal of hearts.
The complement of: مِّن رَّبِّكُمْ (from your Lord) with (advice) has elevated the status of Qur'anic advice to a much higher level. It is telling us that this advice is not coming from a helpless human being that does not hold the keys to anyone's profit and loss or reward and punishment, nor has any credibility of his own. Instead, the advice is from the merciful Lord whose Word admits of no error, and whose promise and warning too are free of any apprehension of some weakness or excuse.
2\. CURE as in: شِفَاءٌ لِّمَا فِي الصُّدُورِ (a cure for what is in your hearts).
The word: شِفَاءٌ (shifa' ) means the removal of disease and: صدُورِ (sudur) is the plural form of: صدر (sadr) which means the chest, and it signifies the heart.
The sense is that the Holy Qur'an is a successful remedy of the diseases of the heart. It corrects and cures it as a prescription of legendary elixir would. The famous Hasan al-Basri (رح) said, ` from this attribute of the Qur'an, we learn that it is a cure for the diseases of the heart specifically, and not that of physical diseases. (Ruh al-Ma` ani)
But, other scholars have said that the Holy Qur'an is a cure for every disease, whether spiritual or physical. However, spiritual diseases are far more harmful for men and women than physical diseases. Then, the treatment of such diseases too is not in everyone's control. Therefore, at this place, only spiritual diseases that relate to the heart have been mentioned. From this it does not necessarily follow that it is not a cure for physical diseases.
Hadith reports and countless experiments of the religious scholars of the Muslim community are witnesses to the fact that the way the Holy Qur'an is a great elixir for diseases of the heart, very similarly, it is the best of treatments for physical diseases also.
As narrated by Sayyidna Abu Said al-Khudri ؓ someone came to Holy Prophet ﷺ and complained that he felt he had a chest problem. He said, ` recite the Qur'an, for Allah Ta` ala says: شِفَاءٌ لِّمَا فِي الصُّدُورِ that is, ` the Qur'an is a cure for all such diseases as are found insides chests.' (Ruh al-Ma` ani from Ibn Marduwayh)
Similarly, according to the narration of Sayyidna Wathilah ibn Asqa' ؓ someone came to the Holy Prophet ﷺ and said that he had a throat problem. He told him the same thing - ` recite the Qur'an'.
Scholars of the Muslim community have compiled the properties and efficacies of the Qur'anic verses in regular books by extracting these partly from narratives of Hadith and the sayings of the Sahabah, and partly from their own experiments and experience. Imam al-Ghazali's work on ` Qur'anic Properties' is well known in this area. Maulana Ashraf ` Ali Thanavi's (رح) "A'mal-i-Qur'anii, an abridgement of this work, has been popular among readers of Urdu for over fifty years. Then, there are so many observations and experiments in this field which prove that different verses of the Holy Qur'an have been a total cure for physical diseases as well. Denying all of them is not possible. However, this much can be conceded that the real purpose of the revelation of the Holy Qur'an is to remove the diseases of the heart and soul while, as a corollary, it is also the most effective treatment of even physical diseases.
This also tells us that those who recite the Holy Qur'an only to treat physical diseases or to seek nothing but the fulfillment of worldly needs are low in sense and high in waywardness. Such people never bother to correct spiritual diseases, nor do they pay any heed to the need of doing things in accordance with the instructions given by the Qur'an. For such people, Iqbal said:
ترا حاصل زیٰس اش جزین نیست کہ ازھم خواندنش آسان بمیری
Your gain from Ya Sin is but that:
By reciting it, death becomes easy.
Though, he is suggesting, had you pondered over its meaning and message, realities and insights, you would have gained much more of its benefits and blessings.
Some research-oriented commentators who have gone deeper into the meanings of the Qur'an have said that the first attribute of the Qur'an, that is, مَّوْعِظَةٌ (maw'izah: advice, good counsel) relates to man's obvious, outward or physically-accomplished deeds known as the Shari` ah. The Holy Qur'an is the best source of the correction and betterment of such deeds. Then, the second attribute: شِفَاءٌ لِّمَا فِي الصُّدُورِ (a cure for what is in your hearts) relates to man's hidden, inward or heart-oriented deeds known as Tariqah and Tasawwuf.
3\. GUIDANCE as in: وَهُدًى (and guidance).
The word: هُدًى (huda) means guidance or the showing of or leading onto the way. The Holy Qur'an invites human beings to the way of truth and faith. It invites them to ponder over the great signs Allah Ta'ala has placed in the near and far ranges of the world, even inside their own person, [ staggering would certainly be the interior distances of the universe within us ] and recognize the creator and master of everything.