إِنَّ اللَّهَ لَا يَظْلِمُ مِثْقَالَ ذَرَّةٍ ۖ وَإِن تَكُ حَسَنَةً يُضَاعِفْهَا وَيُؤْتِ مِن لَّدُنْهُ أَجْرًا عَظِيمًا
Surely! Allah wrongs not even of the weight of a speck of dust, but if there is any good (done), He doubles it, and gives from Him a great reward. (Surah An-Nisa , aayah 40)
Allah states that He does not treat any of His servants with injustice on the Day of Resurrection, be it the weight of a mustard seed or a speck of dust. Rather, Allah shall reward them for this action and multiply it, if it were a good deed. For instance, Allah said,
(And We shall set up balances of justice) Allah said that Luqman said,
(O my son! If it be (anything) equal to the weight of a mustard seed, and though it be in a rock, or in the heavens or in the earth, Allah will bring it forth). Allah said,
(That Day mankind will proceed in scattered groups that they may be shown their deeds. So whosoever does good equal to the weight of a speck of dust shall see it. And whosoever does evil equal to the weight of a speck of dust shall see it.) The Two Sahihs recorded the long Hadith about the intercession that Abu Sa`id Al-Khudri narrated, and in which the Messenger of Allah said,
(Allah then says, “Go back, and take out of the Fire everyone in whose heart you find the weight of a mustard seed of faith”) In another narration, Allah says,
(“Whosoever had the least, least, least speck of faith, take him out of the Fire,” and they will take out many people.) Abu Sa`id then said, “Read, if you will,
(Surely! Allah wrongs not even of the weight of a speck of dust).”
Source: Tafseer Ibn Katheer, Darussalam English Publication
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