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 And if We so willed, We could indeed take away whatever We have revealed unto thee, and in that [state of need] thou wouldst find none to plead in thy behalf before Us. 86 Except [We have left it with you] as a mercy from your Lord. Indeed, His favor upon you has ever been great. 87 Say: If men and jinn should combine together to bring the like of this Quran, they could not bring the like of it, though some of them were aiders of others. 88 And We have explained to man, in this Qur'an, every kind of similitude: yet the greater part of men refuse (to receive it) except with ingratitude! 89 and so they say: "[O Muhammad,] we shall not believe thee till thou cause a spring to gush forth for us from the earth, 90 "Or (until) thou have a garden of date trees and vines, and cause rivers to gush forth in their midst, carrying abundant water; 91 Or thou cause the heaven to fall upon us piecemeal, as thou hast pretended, or bring Allah and the angels as a warrant; 92 or you have a house made of gold; or you ascend to heaven; and we will not believe in your ascension until you send down to us a Book that we can read." Tell them, "Holy is my Lord. I am but a human being sent as a messenger." 93