اللَّهُمَّ إِنْ كَانَ مُحْسِنًا فَزِدْ فِي إِحْسَانِهِ وَإِنْ كَانَ مُسِيئًا فَتَجَاوَزْ عَنْ سَيِّئَاتِهِ
Allahumma in kana muhsinan fazid fi ihsanihi wa in kana musi'an fatajawaz 'an sayyi'atih
O Allah, if he was a doer of good, then increase his good deeds, and if he was a wrongdoer, then overlook his misdeeds.
A janazah du'a that covers both possibilities without judgment. You do not know the deceased's true state — only Allah does. If they were good, ask for more. If they were bad, ask for forgiveness. The beauty is in the humility: you do not declare them righteous or sinful. You present both scenarios and let Allah's knowledge and mercy determine the outcome.
Related Du'as
إِنَّ لِلَّهِ مَا أَخَذَ وَلَهُ مَا أَعْطَى وَكُلُّ شَيْءٍ عِنْدَهُ بِأَجَلٍ مُسَمًّى
To Allah belongs what He took, and to Him belongs what He gave, and everything with Him has an appointed time.
Sahihاللَّهُمَّ اغْفِرْ لِحَيِّنَا وَمَيِّتِنَا وَصَغِيرِنَا وَكَبِيرِنَا وَذَكَرِنَا وَأُنْثَانَا وَشَاهِدِنَا وَغَائِبِنَا
O Allah, forgive our living and our dead, our young and our old, our males and our females, our present and our absent.
Sahihاللَّهُمَّ إِنِّي أَعُوذُ بِكَ مِنْ عَذَابِ الْقَبْرِ وَمِنْ عَذَابِ جَهَنَّمَ وَمِنْ فِتْنَةِ الْمَحْيَا وَالْمَمَاتِ وَمِنْ شَرِّ فِتْنَةِ الْمَسِيحِ الدَّجَّالِ
O Allah, I seek refuge in You from the punishment of the grave, from the torment of the Fire, from the trials of life and death, and from the evil of the trial of the False Messiah.
Sahihاللَّهُمَّ إِنِّي أَسْأَلُكَ حُسْنَ الْخَاتِمَةِ وَأَعُوذُ بِكَ مِنْ سُوءِ الْخَاتِمَةِ، اللَّهُمَّ اجْعَلْ خَيْرَ أَعْمَالِنَا خَوَاتِمَهَا وَخَيْرَ أَيَّامِنَا يَوْمَ نَلْقَاكَ
O Allah, I ask You for a good ending and I seek refuge in You from a bad ending. O Allah, make the best of our deeds their conclusions and the best of our days the day we meet You.
Hasan