Only Allaah Can Remove Harm
وَإِن يَمۡسَسۡكَ ٱللَّهُ بِضُرّٖ فَلَا كَاشِفَ لَهُۥٓ إِلَّا هُوَۖ وَإِن يُرِدۡكَ بِخَيۡرٖ فَلَا رَآدَّ لِفَضۡلِهِۦۚ يُصِيبُ بِهِۦ مَن يَشَآءُ مِنۡ عِبَادِهِۦۚ وَهُوَ ٱلۡغَفُورُ ٱلرَّحِيمُ ١٠٧
<<And if Allah should touch you with adversity, there is none who can remove it except Allah; and if He intends for you good, then there is no repeller of His bounty. He causes it to reach whom He wills of His servants. And He is the Forgiving, the Merciful>>
AbdurRahman bin Nasr as-Sa’adi
This is one of the greatest proofs that Allaah alone is worthy of worship, for verily He is the One who grants benefit or harm, the One who provides and the One who prevents.
If any harm such as poverty and sickness etc. befalls you << there is none who can remove it except Allaah >>. This is because if all (those from) the creation gathered together in order to bring forth any type of benefit they would be unable to do so unless Allaah wrote it for them (thus allowing it). Likewise if (those from) the creation of Allaah gathered in order to cause harm to anyone, they would be unable to do so unless Allaah allowed it.
This is why Allaah says: <<and if He intends for you good, then there is no repeller of His bounty. >> meaning, that it is not possible for any of Allaah’s creation to reject His Good and His Kindness, as Allaah says: << Whatever Allah grants people of His mercy – none can withhold it; and whatever He withholds – none can release it thereafter>> [Fatir: 2]
<< He causes it to reach whom He wills of His servants. >> meaning Allaah selects whomsoever He wills with His Mercy from His creation, verily Allah possesses all Excellence and Greatness.
<<He is the Most Forgiving>> of all the mistakes of the creation, He grants His slave success through the means of His forgiveness, consequently if a slave sins Allah forgives his sins regardless of whether they are major sins or minor sins. He is Ar-Raheem (the Merciful), thus His Mercy encompasses all that exists, hence it is not possible to exist without His goodness even for the (time of) a blink of an eye.
Therefore a slave of Allaah becomes aware of the clear evidence that illustrates that Allaah exclusively is the One who bestows blessings in addition to clearing afflictions and granting good and removing evils and hardships.
There is none from the creation who possesses an iota of this ability to unless it is by Allaah’s permission. Therefore this knowledge obligates upon us an awareness of the reality that Allaah Alone is the Truth and what others call to other than him is merely falsehood.
[From: Tayseer al-Kareem ar-Rahman fee Tafseer Klam al-Manan 3/224]