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 withdraw that which We have revealed unto thee, then wouldst thou find no guardian for thee against Us in respect thereof. 86 (Whatever you have received) is nothing but grace from your Lord. Indeed His favour to you is great. 87 Say: "If the mankind and the jinns were together to produce the like of this Quran, they could not produce the like thereof, even if they helped 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 will not put faith in thee till thou cause a spring to gush forth from the earth for us; 90 or, until you own a garden of palms and vines and cause rivers to gush forth with abundant water in them; 91 "Or thou cause the sky to fall in pieces, as thou sayest (will happen), against us; or thou bring Allah and the angels before (us) face to face: 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