COMMENTARY on 4:40
Mustafa Khattab:

Translation:
Indeed, Allah never wrongs ˹anyone˺—even by an atom’s weight.14 And if it is a good deed, He will multiply it many times over and will give a great reward out of His grace.
Commentary:
14   lit., the smallest particle of dust (ⱬarrah).

 

A. Yusuf Ali:

Translation:
Allah is never unjust in the least degree: If there is any good (done), He doubleth it, and giveth from His own presence a great reward. 559
Commentary:

559  Any little good of our own comes from the purity of our heart. Its results in the world are doubled and multiplied by Allah's grace and mercy; but an even greater reward comes from His own Presence, His good pleasure, which brings us nearer to Him (Cf. 28:75 and 33:45).

 

Muhammad Asad:

Translation:
Verily, God does not wrong [anyone] by as much as an atom's weight; and if there be a good deed, He will multiply it, and will bestow out of His grace 51 a mighty reward.
Commentary:
51  Lit., "from himself "- i.e., far in excess of what the doer of good may have merited.