Hadith 1438

Az-Zubair bin al-’Awwam (رضي الله عنه) said: This verse was revealed when we were present with the Messenger of Allah () : `And fear the Fitnah (affliction and trial) which affects not in particular (only) those of you who do wrong (but it may afflict all the good and the bad people)`. (al-Anfal [8:25]). We started saying: “What is this fitnah? And we never thought that it would happen as it did.”

حَدَّثَنَا أَسْوَدُ بْنُ عَامِرٍ، حَدَّثَنَا جَرِيرٌ، قَالَ سَمِعْتُ الْحَسَنَ، قَالَ قَالَ الزُّبَيْرُ بْنُ الْعَوَّامِ نَزَلَتْ هَذِهِ الْآيَةُ وَنَحْنُ مُتَوَافِرُونَ مَعَ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ‏<a href="javascript:openquran(7,25,25)" id="q8" name="q8"><c_q8>{‏وَاتَّقُوا فِتْنَةً لَا تُصِيبَنَّ الَّذِينَ ظَلَمُوا مِنْكُمْ خَاصَّةً‏}</c_q8></a>‏ فَجَعَلْنَا نَقُولُ مَا هَذِهِ الْفِتْنَةُ وَمَا نَشْعُرُ أَنَّهَا تَقَعُ حَيْثُ وَقَعَتْ‏.‏

Reference: 5313610
In-book reference: Book 7, Hadith 1438
Hadith 1438 - The Musnad of az-Zubair bin al-'Awwam - Musnad Ahmad - Sunnah.com