سورة Al-Ahqaf ( The Curved Sand-hills ) - الآية 8

What! They dare say, “He has fabricated it”? Say (O dear Prophet Mohammed – peace and blessings be upon him), “If I have fabricated it, then (I know that) you have no power to support me against Allah; He well knows the matters you are involved in; He is Sufficient as a Witness between me and you; and He only is the Oft Forgiving, the Most Merciful.”