فَٱلَّذِينَ ءَامَنُوا۟ وَعَمِلُوا۟ ٱلصَّـٰلِحَـٰتِ لَهُم مَّغْفِرَةٌ وَرِزْقٌ كَرِيمٌ Qur’an Al-Hajj (22:50)Fa a lla th eena a manoo waAAamiloo a l ssa li ha ti lahum maghfiratun warizqun kareem un
See 8:4 and the corresponding note [5].
The "sustenance" must be construed in the widest sense, spiritual as well as intellectual and physical. The reward of righteousness is far more generous than any merit there may be in the creature following the Will of his Creator.