They ask you about "the spirit". Say: "The spirit descends by the command of my Lord, but you have been given only a little knowledge." 85 And if We willed, We could surely do away with that which We revealed to you. Then you would not find for yourself concerning it an advocate against 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: Verily, though mankind and the jinn should assemble to produce the like of this Qur'an, they could not produce the like thereof though they were helpers one of another. 88 We have mentioned in this Quran all kinds of examples for the human being, but most human beings turn away in disbelief. 89 And they say: We will not put faith in thee till thou cause a spring to gush forth from the earth for us; 90 or you have a garden of date palms and vines, and cause streams to flow plentifully in the midst of them; 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 thou have a house of gold; or thou ascend up into heaven, and even then we will put no faith in thine ascension till thou bring down for us a book that we can read. Say (O Muhammad): My Lord be Glorified! Am I aught save a mortal messenger? 93