Musnad Ahmad 1
It was narrated that Qais said:
Abu Bakr stood up and praised and glorified Allah, then he said: O people, you recite this verse: `O you who believe! Take care of your ownselves. If you follow the (right) guidance (and enjoin what is right (Islamic Monotheism and all that Islam orders one to do) and forbid what is wrong (polytheism, disbelief and all that Islam has forbidden)] no hurt can come to you from those who are in error` (al-Ma'idah 5:105]. We heard the Messenger of Allah (ﷺ) say: `lf the people see evil and do not change it, soon Allah will send His punishment upon them all.`
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ نُمَيْرٍ، قَالَ أَخْبَرَنَا إِسْمَاعِيلُ يَعْنِي ابْنَ أَبِي خَالِدٍ، عَنْ قَيْسٍ، قَالَ قَامَ أَبُو بَكْرٍ رَضِيَ اللَّهُ عَنْهُ فَحَمِدَ اللَّهَ وَأَثْنَى عَلَيْهِ ثُمَّ قَالَ يَا أَيُّهَا النَّاسُ إِنَّكُمْ تَقْرَءُونَ هَذِهِ الْآيَةَ ‏{‏يَا أَيُّهَا الَّذِينَ آمَنُوا عَلَيْكُمْ أَنْفُسَكُمْ لَا يَضُرُّكُمْ مَنْ ضَلَّ إِذَا اهْتَدَيْتُمْ‏}‏ وَإِنَّا سَمِعْنَا رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ إِنَّ النَّاسَ إِذَا رَأَوْا الْمُنْكَرَ فَلَمْ يُنْكِرُوهُ أَوْشَكَ أَنْ يَعُمَّهُمْ اللَّهُ بِعِقَابِهِ‏.‏