Sahih al-Bukhari 6921
صحيح البخاري#6921Sahihحَدَّثَنَا خَلاَّدُ بْنُ يَحْيَى، حَدَّثَنَا سُفْيَانُ، عَنْ مَنْصُورٍ، وَالأَعْمَشِ، عَنْ أَبِي وَائِلٍ، عَنِ ابْنِ مَسْعُودٍ ـ رضى الله عنه ـ قَالَ قَالَ رَجُلٌ يَا رَسُولَ اللَّهِ أَنُؤَاخَذُ بِمَا عَمِلْنَا فِي الْجَاهِلِيَّةِ قَالَ " مَنْ أَحْسَنَ فِي الإِسْلاَمِ لَمْ يُؤَاخَذْ بِمَا عَمِلَ فِي الْجَاهِلِيَّةِ، وَمَنْ أَسَاءَ فِي الإِسْلاَمِ أُخِذَ بِالأَوَّلِ وَالآخِرِ ".
Narrated Ibn Mas`ud:A man said, "O Allah's Messenger (ﷺ)! Shall we be punished for what we did in the pre-Islamic Period of ignorance?" The Prophet (ﷺ) said, "Whoever does good in Islam will not be punished for what he did in the Pre-Islamic Period of ignorance and whoever does evil in Islam will be punished for his former and later (bad deeds)
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 88:4