אֲשֶׁר֩ יְדַבֵּ֨ר הַנָּבִ֜יא בְּשֵׁ֣ם יְהוָ֗ה וְלֹֽא־יִהְיֶ֤ה הַדָּבָר֙ וְלֹ֣א יָב֔וֹא ה֣וּא הַדָּבָ֔ר אֲשֶׁ֥ר לֹא־דִבְּר֖וֹ יְהוָ֑ה בְּזָדוֹן֙ דִּבְּר֣וֹ הַנָּבִ֔יא לֹ֥א תָג֖וּר מִמֶּֽנּוּ׃ (ס)
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; the prophet hath spoken it presumptuously, thou shalt not be afraid of him.
Targum Jonathan on Deuteronomy
When a false prophet speaketh in the Name of the Lord, and the thing doth not come to pass, or be not confirmed, it is a word which the Lord hath not spoken; the false prophet spake it in presumption; fear him not.