Allah has sent down the Best Statement, a Book (this Quran), its parts resembling each other (in goodness and truth) (and) oft-repeated. The skins of those who fear their Lord shiver from it (when they recite it or hear it). Then their skin and their heart soften to the remembrance of Allah. That is the guidance of Allah. He Guides therewith whom He wills; and whomever Allah sends astray, for him there is no guide.” Surah Az-Zumar:23