لِيُكَفِّرَ ٱللَّهُ عَنْهُمْ أَسْوَأَ ٱلَّذِى عَمِلُوا۟ وَيَجْزِيَهُمْ أَجْرَهُم بِأَحْسَنِ ٱلَّذِى كَانُوا۟ يَعْمَلُونَ Qur’an Az-Zumar (39:35)Liyukaffira All a hu AAanhum aswaa alla th ee AAamiloo wayajziyahum ajrahum bia h sani alla th ee k a noo yaAAmaloon a
The conjunction (lam in Arabic, translated "so that") indicates here the results, not the purpose. Allah's Reward is so bounteous, that if we truly and sincerely put our will into His keeping, He will remove the consequences not only of our minor faults but of the worst of our sins, and judge us according to the very best of our deeds.