Deuteronomy 18:22

when a prophet speaks in the name of the Lord , if the word does not come to pass or come true, that is a word that the Lord has not spoken ; the prophet has spoken it presumptuously . You need not be afraid of him.

If what a prophet proclaims in the name of the Lord does not take place or come true, that is a message the Lord has not spoken. That prophet has spoken presumptuously, so do not be alarmed.

When a prophet speaketh in the name of the Lord, if the thing follow not, nor come to pass, that is the thing which the Lord hath not spoken, but the prophet hath spoken it presumptuously : thou shalt not be afraid of him. Deuteronomy 17 Books Deuteronomy 19