These are nothing but words of prophecy
Figuratively: these statements are unreasoned and unfounded, and they sound as if they were uttered by prophecy.
("One who says to his friend, 'I am selling you a portion in a vineyard' ... Rabbi Yossi said: 'These are nothing but words of prophecy.'" - Bava Batra 12a.)
Translation
Expression (Hebrew)
אֵין אֵלּוּ אֶלָּא דִּבְרֵי נְבִיאוּת
Definition (Hebrew)
בְּהַשְׁאָלָה: הַדְּבָרִים הָאֵלּוּ אֵינָם מְנֻמָּקִים וְאֵינָם מְבֻסָּסִים וְהֵם נִשְׁמָעִים כְּאִלּוּ נִתְּנוּ בְּצוּרַת "נְּבוּאָה", אֶלָּא שֶׁבְּיָמֵינוּ אֵין נְבִיאִים.
("הָאוֹמֵר לַחֲבֵרוֹ מְנָת בַּכֶּרֶם אֲנִי מוֹכֵר לְךָ ... אָמַר ר' יוֹסֵי :אֵין אֵלּוּ אֶלָּא דִּבְרֵי נְבִיאוּת "- בָּבָא בָּתְרָא יב ע"א).