﴿ وَقُرْءَانًۭا فَرَقْنَٰهُ لِتَقْرَأَهُۥ عَلَى ٱلنَّاسِ عَلَىٰ مُكْثٍۢ وَنَزَّلْنَٰهُ تَنزِيلًۭا ﴾

“[bearing] a discourse which We have gradually unfolded, so that thou might read it out to mankind by stages, seeing that We have bestowed it from on high step by step, as [one] revelation.”

(And (it is) a Qur'an) And We have sent Gabriel with the Qur'an (that We have divided) We explained therein the lawful and unlawful, the commands and prohibitions, (that thou mayst recite it unto mankind at intervals) in a composed manner, deliberately and thoughtfully, (and We have revealed it by (successive) revelation) We have exposited it clearly; it is also said that this means: We have sent Gabriel with the Qur'an in different phases, each time with two or three verses, and so on and so forth.