It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both); he said: "The Qur'an was sent down all at once (from the Preserved Tablet) to the lowest heaven, then after that it was sent down (little by little) over a period of twenty years." And concerning the saying of Allah Almighty: "And they do not bring you any example except that We bring you the truth and a better explanation" [Surah al-Furqan: 33] , he said that what is meant is this verse: "And (it is) a Qur'an which We have divided so that you may recite it to the people at intervals, and We have sent it down in stages." [Surah al-Isra': 106] The chain of this hadith is sahih (authentic), and the two Shaykhs did not record it.