NASAI 5523: from Ibn Yisāf —
What supplication did the Messenger of Allah [SAW] say the most before he died? She said: "The supplication that he said the most was: 'Allahumma, inni a'udhu bika min sharri ma 'amiltu wa min sharri ma lam a'mal ba'd (O Allah, I seek refuge with You from the evil of what I have done, and from the evil of what I have not done yet.)'"

النسائي ٥٥٢٣: عن ابن يساف —
أَنَّهُ سَأَلَ عَائِشَةَ زَوْجَ النَّبِيِّ ﷺ مَا كَانَ أَكْثَرَ مَا يَدْعُو بِهِ رَسُولُ اللَّهِ ﷺ قَبْلَ مَوْتِهِ قَالَتْ كَانَ أَكْثَرَ مَا كَانَ يَدْعُو بِهِ اللَّهُمَّ إِنِّي أَعُوذُ بِكَ مِنْ شَرِّ مَا عَمِلْتُ وَمِنْ شَرِّ مَا لَمْ أَعْمَلْ


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Nasāʾī > Seeking Refuge with Allah > § Seeking Refuge from the Evil of One's Actions, and...
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