إِلَّا مَن تَابَ وَآمَنَ وَعَمِلَ عَمَلًا صَالِحًا فَأُولَٰئِكَ يُبَدِّلُ اللَّهُ سَيِّئَاتِهِمْ حَسَنَاتٍ ۗ وَكَانَ اللَّهُ غَفُورًا رَّحِيمًا
Illā man tāba wa-āmana wa-‘amila swālihan faulaā’ika yubaddilul-lāhu sayyi’ātihim hasanāt; wakānal-lāhu ghafūran rahīmā
Except for those who repent, believe, and do righteous work. For them Allah will replace their evil deeds with good. And ever is Allah Forgiving and Merciful.
(Sūrat al-Furqān, No 25, Āyat 70)
When a believer commits a sin, it is a sign of an unhealthy soul, one which is not on its natural alignment of servitude to its Creator. For such a sickness there must be treatment sought. Just like physical sickness is cured through taking medicine and abstaining from certain things, the spiritual sickness of disobedience must be cured through repentance and abstaining from indulging in desires.
Quranic repentance refers to a connection between a human being and Allah ‘azza wajall in which Allah grants a virtue and superiority to the human being, putting him on a path to happiness. This is for servants who seek purity and are loved by Allah. Repentance sometimes follows sins and sometimes it is a return to the mercy of Allah subhānahu wata‘ālā upon someone, as when the Quran says that Allah accepted the repentance of the Prophet (s), the Immigrants and the Helpers who followed him, without mentioning any sins (Q 9:117).
Repentance is a door that is always open for the person who sins. It is the grace and mercy of Allah (swt) that He welcomes back the one who has turned away from Him. According to justice, punishment is decreed for the person who disobeys Allah, but exceptions are made for those who repent and turn back to Allah. The Prophet sallal-lāhu ‘alayhi wa-ālihi wasallam has said: One who repents from a sin is like one who has not committed it (Bihār al-Anwār, v. 6, p. 21).
Repentance has certain conditions. As outlined in the verse above, the repentance must be manifested in increased faith and good deeds. It is not just felt by the heart or verbalized on the tongue. It is also put into action. The regret is channeled into good deeds – acts that reflect the renewed desire to please Allah ‘azza wajall and make up for turning away from Him.
Then the verse makes an amazing statement. For one who truly repents, not only are the sins forgiven but they are changed into good deeds. How does this happen? The changing of sins to good deeds can be understood in the following ways:
1) When a person repents and sincerely turns to Allah, his whole being is infused with a different spirit. It creates an inner transformation that affects everything he does. Whatever sins he committed, he will now make amends for them and do things very differently. Instead of evil deeds, good deeds will come forth from him. This will be possible with tawfīq from Allah which is a result of faith and repentance.
2) The grace and mercy of Allah encompasses the repentant believer and past sins are erased. Abū Dharr al-Ghaffārī narrates from the Prophet (s) who told him that on the Day of Judgement a person will be brought forward and informed about his minor sins. He will acknowledge them and will be very afraid of his major sins. At that moment Allah will choose to give him a special grace and will order that his sins be changed to good deeds in his book. The person will declare, ‘I have committed sins that I don’t see here’. Abū Dharr narrates that at that time the Prophet (s) smiled broadly and recited the above verse – For them Allah will replace their evil deeds with good.
3) A third understanding is that the evil deeds mentioned here are not the actual sins but the negative effect of the sins on the soul. When a person repents, that negative effect is annulled and replaced with a positive surge of spirituality due to repentance and faith.
It is possible that the verse encompasses all the above three understandings.
As we get ready to welcome the Holy month of Ramadan, a month of repentance and seeking forgiveness, we must increase the intensity with which we return to Allah. The journey towards Allah cannot be traversed if we are burdened with the baggage of sins. It is only after shedding that burden and becoming lighter that we can move swiftly ahead. As the Prophet (s) said when he welcomed the holy month: O people, your souls are dependent on your deeds, therefore release them by asking for forgiveness. Your backs are burdened with your weight [of sins], so lighten their burden by lengthening prostrations (sajdah). May the Almighty help us to return to Him in this month and gain His mercy and forgiveness and make us from those whose sins are changed into good deeds.
Sources: Shaykh Tabarsī, Tafsīr Majma‘ al Bayān, Āyatullāh Nāsir Makārim Shirāzī (Ed.), Tafsīr-e Namūneh; https://en.wikishia.net/view/