It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "A time will come upon my Ummah in which the reciters (of the Qur'an) will be many while the jurists (those with deep understanding of the religion) will be few; knowledge will be taken away and harj will become widespread." The Companions asked: "O Messenger of Allah! What is harj?" He (peace and blessings be upon him) said: "Killing among yourselves. Then after that a time will come in which people will recite the Qur'an but it will not go beyond their throats. Then after that an era will come in which the hypocrite, the disbeliever and the one who associates partners with Allah will dispute with the believer using the very same kind of words that the believer (apparently) says." This hadith has an authentic (sahih) chain of narration, but the two Shaykhs (Bukhari and Muslim) did not record it.