They ask you about the Spirit. Say, "The Spirit comes by the command of my Lord. You have been given very little knowledge. 85 If We pleased We could take away that which We have revealed to you then you should find none to guard you against Us, 86 (Whatever you have received) is nothing but grace from your Lord. Indeed His favour to you 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 And certainly We have explained for men in this Quran every kind of similitude, but most men do not consent to aught but denying. 89 And say: "We will not believe you until you make a spring of water gush forth from the earth for us; 90 "Or (until) thou have a garden of date trees and vines, and cause rivers to gush forth in their midst, carrying abundant water; 91 or till thou makest heaven to fall, as thou assertest, on us in fragments, or thou bringest God and the angels as a surety, 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