Sahih Bukhari Volume 1, Book 3, Hadith 100

حَدَّثَنَا إِسْمَاعِيلُ بْنُ أَبِي أُوَيْسٍ، قَالَ حَدَّثَنِي مَالِكٌ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَبْدِ اللَّهِ بْنِ عَمْرِو بْنِ الْعَاصِ، قَالَ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ ‏"‏ إِنَّ اللَّهَ لاَ يَقْبِضُ الْعِلْمَ انْتِزَاعًا، يَنْتَزِعُهُ مِنَ الْعِبَادِ، وَلَكِنْ يَقْبِضُ الْعِلْمَ بِقَبْضِ الْعُلَمَاءِ، حَتَّى إِذَا لَمْ يُبْقِ عَالِمًا، اتَّخَذَ النَّاسُ رُءُوسًا جُهَّالاً فَسُئِلُوا، فَأَفْتَوْا بِغَيْرِ عِلْمٍ، فَضَلُّوا وَأَضَلُّوا ‏"‏‏.‏ قَالَ الْفِرَبْرِيُّ حَدَّثَنَا عَبَّاسٌ قَالَ حَدَّثَنَا قُتَيْبَةُ حَدَّثَنَا جَرِيرٌ عَنْ هِشَامٍ نَحْوَهُ

Narrated By 'Abdullah bin 'Amr bin Al' As : I heard Allah's Apostle saying, "Allah does not take away the knowledge, by taking it away from (the hearts of) the people, but takes it away by the death of the religious learned men till when none of the (religious learned men) remains, people will take as their leaders ignorant persons who when consulted will give their verdict without knowledge. So they will go astray and will lead the people astray."