They ask thee concerning the Spirit (of inspiration). Say: "The Spirit (cometh) by command of my Lord: of knowledge it is only a little that is communicated to you, (O men!)" 85 If We pleased We could take away what We have revealed to you. Then you will not find any one to plead for it with Us, 86 (Whatever you have received) is nothing but grace from your Lord. Indeed His favour to you is 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 And verily We have displayed for mankind in this Qur'an all kind of similitudes, but most of mankind refuse aught save disbelief. 89 They declare, "We will never believe in you until you cause a spring to flow for us from the earth; 90 or you have a garden of date palms and vines, and cause streams to flow plentifully in the midst of them; 91 or, until you cause the sky to fall upon us in pieces, as you have claimed, or, as a surety bring Allah with the angels in front; 92 "Or thou have a house adorned with gold, or thou mount a ladder right into the skies. No, we shall not even believe in thy mounting until thou send down to us a book that we could read." Say: "Glory to my Lord! Am I aught but a man,- a messenger?" 93