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 surely take away that which We have revealed to you by inspiration (i.e. this Quran). Then you would find no protector for you against Us in that respect. 86 except through the special mercy of your Lord. His favours towards you has been great indeed. 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 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 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 you should have a house of gold, or you should ascend into heaven, and we will not believe in your ascending until you bring down to us a book which we may read. Say: Glory be to my Lord; am I aught but a mortal apostle? 93