How can a person who has sincerely repented of a grave sin committed in their youth, and who has since begun to perform good deeds and draw closer to God, overcome the memory of this sin that causes them distress and fear, especially when reading the Quran or hearing verses that speak of sins similar to theirs?

If a person repents with sincere repentance, fulfilling its conditions, then Allah accepts his repentance, and he becomes as if he had never sinned, for Allah Almighty says: "And He is the One who accepts repentance from His servants and pardons sins." The warning in the Qur’an applies to those who do not repent. Therefore, one should increase in performing good deeds, because "Indeed, good deeds do away with ill deeds."