Sayyiduna Hudhayfah (may Allah be pleased with him) says: The Messenger of Allah (peace and blessings of Allah be upon him) was asked about the Hour (Day of Judgment). In response, he recited this verse: "Its knowledge is only with my Lord. None will reveal its time except Him." (Surah Al-A'raf: 187) Then he said: "However, I will inform you of its signs and the matters that will occur before it. Before it, there will be tribulation (fitnah) and killing (harj)." The Companions said: We know the meaning of tribulation, but what is meant by harj? The Prophet (peace and blessings of Allah be upon him) said: "It is a word from the Abyssinian language; it means 'killing.' And (before the Hour) there will be estrangement among people; no one will recognize anyone else."