﴿ قُل لِّلَّذِينَ كَفَرُوٓا۟ إِن يَنتَهُوا۟ يُغْفَرْ لَهُم مَّا قَدْ سَلَفَ وَإِن يَعُودُوا۟ فَقَدْ مَضَتْ سُنَّتُ ٱلْأَوَّلِينَ ﴾

“Tell those who are bent on denying the truth that if they desist, all that is past shall be forgiven them; but if they revert [to their wrongdoing], let them remember what happened to the like of them in times gone by.”

It is the principle of Islam that the individual is rewarded according to his deeds. However, by His grace the Almighty God has made special exemptions to this general principle: when a man is truly repentant, he will not be punished thereafter for his earlier deeds. Suppose a man spent his life in ungodliness, then he received the light of guidance, became a true believer and adopted the righteous life, in this case, he will be forgiven for the evil deeds done by him earlier; he will not be seized on the basis of his earlier sins.