Quran

إِنَّ ٱللَّهَ لَا يَظۡلِمُ مِثۡقَالَ ذَرَّةٖۖ وَإِن تَكُ حَسَنَةٗ يُضَٰعِفۡهَا وَيُؤۡتِ مِن لَّدُنۡهُ أَجۡرًا عَظِيمٗا

Indeed, Allah does not do injustice, [even] as much as an atom's weight; while if there is a good deed, He multiplies it and gives from Himself a great reward