It is narrated from Sayyiduna Ubayy bin Ka'b (may Allah be pleased with him) concerning the saying of Allah Almighty "And the earth and the mountains are lifted up and crushed with a single crushing" [Surah al-Haqqah: 14] , that he said: The two of them (the earth and the mountains) will be crushed to pieces and fall as dust upon the faces of the disbelievers, not upon the faces of the believers; and this is the saying of Allah Almighty: "And many faces that Day will have dust upon them, darkness covering them." [Surah Abasa: 40-41] This hadith has a sahih (authentic) chain of narration, but the two Shaykhs (Bukhari and Muslim) did not record it.