It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Prophet of Allah (peace and blessings be upon him) said: "In the last times, such a severe affliction will descend upon my Ummah from their rulers that no harsher calamity will have ever been heard of before, until the spacious earth becomes narrow for them and the earth is filled with oppression and tyranny. The believer will find no refuge in which to shelter from oppression. Then Allah, the Mighty and Majestic, will raise up a man from my family (itrah) who will fill the earth with equity and justice just as it had been filled with oppression and tyranny. All the dwellers of the heavens and the dwellers of the earth will be pleased with him. The earth will not store away any portion of its produce except that it will bring it forth, and the sky will not hold back any drop of rain except that Allah will pour it down upon them in abundance. He will live among them for seven, eight or nine years. Seeing the good that Allah, the Mighty and Majestic, will have bestowed upon the people of the earth, the living will wish that the dead were alive." The chain of this hadith is authentic (sahih), but the two Shaykhs (Bukhari and Muslim) did not record it.