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 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 (It is naught) save mercy from thy Lord. Lo! His kindness unto thee was ever 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 indeed We have illustrated all kinds of examples in the Qur’an for mankind – so most men did not accept, except to be ungrateful. 89 They say: "We shall not believe in thee, until thou cause a spring to gush forth for us from the earth, 90 or that there be a garden of palms and vines for you and then you cause rivers to abundantly flow forth through them; 91 Or, let chunks of sky fall over us, as you assert (you will); or, bring God and the angels as a surety; 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