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bukhari:7114Khalāad > Misʿar > Ḥabīb b. Abū Thābit > Abū al-Shaʿthāʾ > Ḥudhayfah

Hudhaifa said, 'In fact, it was hypocrisy that existed in the lifetime of the Prophet ﷺ but today it is Kufr (disbelief) after belief.'  

البخاري:٧١١٤حَدَّثَنَا خَلاَّدٌ حَدَّثَنَا مِسْعَرٌ عَنْ حَبِيبِ بْنِ أَبِي ثَابِتٍ عَنْ أَبِي الشَّعْثَاءِ عَنْ حُذَيْفَةَ قَالَ

إِنَّمَا كَانَ النِّفَاقُ عَلَى عَهْدِ النَّبِيِّ ﷺ فَأَمَّا الْيَوْمَ فَإِنَّمَا هُوَ الْكُفْرُ بَعْدَ الإِيمَانِ