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 so willed, We could indeed take away whatever We have revealed unto thee, and in that [state of need] thou wouldst find none to plead in thy behalf before Us. 86 excepting by some mercy of thy Lord; surly His favour to thee is great. 87 Say, "If mankind and the jinn gathered in order to produce the like of this Qur'an, they could not produce the like of it, even if they were to each other assistants." 88 In this Quran, We have set out all kinds of examples for people, yet most of them persist in denying the truth. 89 And they say, "We will not believe you until you break open for us from the ground a spring. 90 "Or you have a garden of date-palms and grapes, and cause rivers to gush forth in their midst abundantly; 91 or cause the sky to fall on us in pieces as you claimed, or bring Allah and the angels before us, face to face; 92 or thou have a house [made] of gold, or thou ascend to heaven - but nay, we would not [even] believe in thy ascension unless thou bring down to us [from heaven] a writing which we [ourselves] could read! Say thou, [O Prophet:] "Limitless in His glory is my Sustainer! Am I, then, aught but a mortal man, an apostle?" 93