صحيح البخاري Sahih Bukhari كتاب العلم The Book of Knowledge
بَابُ رَفْعِ الْعِلْمِ وَظُهُورِ الْجَهْلِ:

(21) Chapter. (What is said regarding) the disappearance of the (religious) knowledge and the appearance of (religious) ignorance.

2 hadith
Hadith 80
حَدَّثَنَا عِمْرَانُ بْنُ مَيْسَرَةَ ، قَالَ : حَدَّثَنَا عَبْدُ الْوَارِثِ ، عَنْ أَبِي التَّيَّاحِ ، عَنْ أَنَسِ بْنِ مَالِكٍ ، قَالَ : قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ : " إِنَّ مِنْ أَشْرَاطِ السَّاعَةِ أَنْ يُرْفَعَ الْعِلْمُ ، وَيَثْبُتَ الْجَهْلُ ، وَيُشْرَبَ الْخَمْرُ ، وَيَظْهَرَ الزِّنَا " .
Narrated Anas: Allah's Apostle said, "From among the portents of the Hour are (the following): -1. Religious knowledge will be taken away (by the death of Religious learned men). -2. (Religious) ignorance will prevail. -3. Drinking of Alcoholic drinks (will be very common). -4. There will be prevalence of open illegal sexual intercourse.
Hadith Reference Sahih Bukhari / The Book of Knowledge / Hadith: 80
Hadith Grading محدثین: أحاديث صحيح البخاريّ كلّها صحيحة
Hadith 81
حَدَّثَنَا مُسَدَّدٌ ، قَالَ : حَدَّثَنَا يَحْيَى ، عَنْ شُعْبَةَ ، عَنْ قَتَادَةَ ، عَنْ أَنَسٍ ، قَالَ : لَأُحَدِّثَنَّكُمْ حَدِيثًا لَا يُحَدِّثُكُمْ أَحَدٌ بَعْدِي ، سَمِعْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ، يَقُولُ : " مِنْ أَشْرَاطِ السَّاعَةِ ، أَنْ يَقِلَّ الْعِلْمُ ، وَيَظْهَرَ الْجَهْلُ ، وَيَظْهَرَ الزِّنَا ، وَتَكْثُرَ النِّسَاءُ ، وَيَقِلَّ الرِّجَالُ حَتَّى يَكُونَ لِخَمْسِينَ امْرَأَةً الْقَيِّمُ الْوَاحِدُ " .
Narrated Anas: I will narrate to you a Hadith and none other than I will tell you about after it. I heard Allah's Apostle saying: From among the portents of the Hour are (the following): -1. Religious knowledge will decrease (by the death of religious learned men). -2. Religious ignorance will prevail. -3. There will be prevalence of open illegal sexual intercourse. -4. Women will increase in number and men will decrease in number so much so that fifty women will be looked after by one man.
Hadith Reference Sahih Bukhari / The Book of Knowledge / Hadith: 81
Hadith Grading محدثین: أحاديث صحيح البخاريّ كلّها صحيحة