كتاب الإيمان
1
The Book of Faith
(51)
Chapter: Encouragement to hasten to do good deeds before the emergence of the Fitnah
(51)
باب الْحَثِّ عَلَى الْمُبَادَرَةِ بِالأَعْمَالِ قَبْلَ تَظَاهُرِ الْفِتَنِ

It is narrated on the authority of Abu Huraira that the Messenger of Allah (ﷺ) observed:

Be prompt in doing good deeds (before you are overtaken) by turbulence which would be like a part of the dark night. During (that stormy period) a man would be a Muslim in the morning and an unbeliever in the evening or he would be a believer in the evening and an unbeliever in the morning, and would sell his faith for worldly goods.
حَدَّثَنِي يَحْيَى بْنُ أَيُّوبَ، وَقُتَيْبَةُ، وَابْنُ، حُجْرٍ جَمِيعًا عَنْ إِسْمَاعِيلَ بْنِ جَعْفَرٍ، - قَالَ ابْنُ أَيُّوبَ حَدَّثَنَا إِسْمَاعِيلُ، - قَالَ أَخْبَرَنِي الْعَلاَءُ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ بَادِرُوا بِالأَعْمَالِ فِتَنًا كَقِطَعِ اللَّيْلِ الْمُظْلِمِ يُصْبِحُ الرَّجُلُ مُؤْمِنًا وَيُمْسِي كَافِرًا أَوْ يُمْسِي مُؤْمِنًا وَيُصْبِحُ كَافِرًا يَبِيعُ دِينَهُ بِعَرَضٍ مِنَ الدُّنْيَا ‏"‏ ‏.‏
Reference : Sahih Muslim 118
In-book reference : Book 1, Hadith 220
USC-MSA web (English) reference : Book 1, Hadith 213
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