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 But on account of mercy from your Lord-- surely His grace to you is abundant. 87 Say thou: if the mankind and the jinn leagued together that they might produce the like of this Qur'an, they could nor produce the like thereof, though one to the other were a backer. 88 For, indeed, many facets have We given in this Qur'an to every kind of lesson [designed] for [the benefit of] mankind! However, most men are unwilling to accept anything but blasphemy 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 thou have a garden of date-palms and grapes, and cause rivers to gush forth therein abundantly; 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 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