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 If We willed, We could take away that We have revealed to thee, then thou wouldst find none thereover to guard thee against Us, 86 Except as a Mercy from your Lord. Verily! His Grace unto you (O Muhammad SAW) is ever great. 87 Say: "If all mankind and all invisible beings would come together with a view to producing the like of this Qur'an, they could not produce its like even though they were to exert all their strength in aiding one another!" 88 And assuredly We have variously propounded for mankind in this Qur'an every kind of similitude, yet most men have refused everything except infidelity. 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 you should have a garden of palms and grapes in the midst of which you should cause rivers to flow forth, gushing out. 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, you come to possess a house of gold; or ascend to the skies, though we shall not believe in your having ascended till you bring down a book for us which we could read." Say: "Glory to my Lord. I am only man and a messenger." 93