Devarim 18:21-22

Orthodox Jewish Bible

²¹ And if thou say in thine lev, How shall we know the word which Hashem hath not spoken?

²² When a navi speaketh b’Shem Hashem, if the thing follow not, nor come to pass, that is the thing which Hashem hath not spoken, but the navi hath spoken it bezadon (in zadon [presumption, arrogance]); thou shalt not be afraid of him.