And they ask thee regarding the spirit; say thou: the spirit is by the command of my Lord, and ye have not been vouchsafed of knowledge save 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 Except as a mercy from thy Lord verily His grace unto thee is ever great. 87 Say: 'If men and jinn banded together to produce the like of this Koran, they would never produce its like, not though they backed one another.' 88 And indeed We have fully explained to mankind, in this Quran, every kind of similitude, but most mankind refuse (the truth and accept nothing) but disbelief. 89 And they say: "We shall not believe in you (O Muhammad SAW), until you cause a spring to gush forth from the earth for us; 90 or till thou possessest a garden of plants and vines, and thou makest rivers to gush forth abundantly all amongst it, 91 or cause the sky to fall into pieces on us - as you believe you can - or bring God and the angels face to face with us, 92 or till thou possessest a house of gold ornament, or till thou goest up into heaven; and we will not believe thy going up till thou bringest down on us a book that we may read. Say: 'Glory be to my Lord. Am I aught but a mortal, a Messenger?' 93