Surely Allah is not ashamed to set forth any parable-- (that of) a gnat or any thing above that; then as for those who believe, they know that it is the truth from their Lord, and as for those who disbelieve, they say: What is it that Allah means by this parable: He causes many to err by it and many He leads aright by it! but He does not cause to err by it (any) except the transgressors,

And when Allah promised you one of the two parties that it shall be yours and you loved that the one not armed should he yours and Allah desired to manifest the truth of what was true by His words and to cut off the root of the unbelievers.