They ask you about revelation. Say, revelation is by the command of your Lord, and that you have been given but little knowledge. 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 Unless your Lord have mercy. His blessings on you are great indeed. 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 We have explained to man, in this Qur'an, every kind of similitude: yet the greater part of men refuse (to receive it) except with ingratitude! 89 And they say: We will by no means believe in you until you cause a fountain 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 you cause the heaven to fall upon us in pieces, as you have pretended, or you 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