Let not him that girds on his armour boast himself as he that puts it off
Figuratively: A person should not boast before completing their task. A proverb warning against arrogance and boasting before accomplishing the mission (original context: let not someone who only girds on battle attire before war boast like one who removes his uniform after victory in battle).
("And the king of Israel answered and said, Tell him: Let not him that girds on his armour boast himself as he that puts it off" — I Kings 20:11, Ahab king of Israel to Ben-Hadad king of Aram)
Translation
Expression (Hebrew)
אַל יִתְהַלֵּל חוֹגֵר כִּמְפַתֵּחַ
Definition (Hebrew)
בְּהַשְׁאָלָה: אַל יִתְרַבְרֵב אָדָם עוֹד בְּטֶרֶם סִיֵּם אֶת מְלַאכְתּוֹ. פִּתְגָּם הַבָּא לְהַזְהִיר אָדָם מִזְּחִיחוּת דַּעַת וְהַשְׁמָעַת דִּבְרֵי הִתְרַבְרְבוּת בְּטֶרֶם בִּצֵּעַ אֶת הַמְּשִׂימָה (הַהֶקְשֵׁר בַּמָּקוֹר: שֶׁלֹּא יִתְרַבְרֵב מִי שָׁרַק חוֹגֵר אֶת בִּגְדֵי הַקְּרָב לִפְנֵי הַמִּלְחָמָה כְּמוֹ אֶחָד שֶׁפּוֹשֵׁט ("מְפַתֵּחַ") אֶת מַדָּיו לְאַחַר נִצְחוֹנוֹ בַּקְּרָב).
("וַיַּעַן מֶלֶךְ יִשְׂרָאֵל וַיֹּאמֶר דַּבְּרוּ אַל יִתְהַלֵּל חֹגֵר כִּמְפַתֵּחַ"-מְלָכִים א כ יָא, אחאב מֶלֶךְ יִשְׂרָאֵל לָבָן הדד מֶלֶךְ ארם)