And they ask you (O Muhammad SAW) concerning the Ruh (the Spirit); Say: "The Ruh (the Spirit): it is one of the things, the knowledge of which is only with my Lord. And of knowledge, you (mankind) have been given only a little." 85 If We willed, We could take away that We have revealed to thee, then thou wouldst find none thereover to guard thee against Us, 86 (It is naught) save mercy from thy Lord. Lo! His kindness unto thee was ever great. 87 Say thou: if the mankind and the jinn leagued together that they might produce the like of this Qur'an, they could nor produce the like thereof, though one to the other were a backer. 88 In this Quran, We have set out all kinds of examples for people, yet most of them persist in denying the truth. 89 They have said, "We shall never believe you until you cause a spring to gush forth from the earth, 90 or till thou possessest a garden of plants and vines, and thou makest rivers to gush forth abundantly all amongst it, 91 or thou cause the skies to fall down upon us in smithereens, as thou hast threatened, or [till] thou bring God and the angels face to face before us, 92 Or you should have a house of gold, or you should ascend into heaven, and we will not believe in your ascending until you bring down to us a book which we may read. Say: Glory be to my Lord; am I aught but a mortal apostle? 93