Tafsir of Ash-Shura 42:19

{Subtle with His servants} He is Kind, with an extreme kindness toward them. His kindness reaches all of them, and it reaches every single one of them in ways they cannot perceive, encompassing both their general states and their specific details.

If you ask: What is the meaning of His saying, {He provides for whom He wills} after stating that His kindness reaches all of them?

I say: All of them are recipients of His kindness; no one is devoid of it. However, kindness has various categories and attributes. Its distribution among servants varies according to the requirements of wisdom and divine management. A certain type of kindness may fall to one servant that does not fall to another, and one may receive a portion with a specific quality that the other does not possess. Whoever is allotted something that is not allotted to another, He has "provided" for him. This is what He meant by {He provides for whom He wills}. Just as He may grant one of two brothers a child while not granting it to the other, even though the latter may have been touched by another blessing that the one with the child was not provided.

{And He is the Powerful} The One of dazzling ability, who prevails over all things.

{The Exalted in Might} The Inaccessible, who cannot be overcome.

{Whoever desires the harvest of the Hereafter - We increase for him in his harvest. And whoever desires the harvest of the world - We give him thereof, but there is not for him in the Hereafter any share.}