He keeps his promise/ his word is his bond/ his yea is yea and his nay is nay
His word is his word. He stands by his word. He believes in the things he says. His word is his word.
("But what man is praised for being known for being divided in his generation and for all knowing that his is one and his is not one in his teachings" - Sefer Shebulei Haleket Hilchot Shamachot Simahan 13, and so: "A man who does not know you sits with us here, a man who is wise in all things, his is one and his is not one in his teachings, he is not the wisest of the many, "Like many Ashkenazi Hasidim, whose fear precedes their wisdom, yet over every word and speech that comes out of his mouth you will be able to build a wall" - Agnon/ Ad Hena, 116)
Translation
Expression (Hebrew)
הֵן שֶׁלּוֹ הֵן וְלָאו שֶׁלּוֹ לָאו
Definition (Hebrew)
כֵּן שֶׁלּוֹ זֶה כֵּן. הוּא עוֹמֵד בְּדִבּוּרוֹ. הוּא אָמִין בִּדְבָרִים שֶׁאוֹמֵר. מִלָּה שֶׁלּוֹ זֶה מִלָּה.
("אֲבָל עַל אֵיזֶה אָדָם מַסְפִּידִין עַל שֶׁיּוֹדְעִין עָלָיו שֶׁהוּא מֻפְלָג בְּדוֹרוֹ וְיוֹדְעִין הַכֹּל שֶׁהֵן שֶׁלּוֹ הֵן וְלָאו שֶׁלֹּא לָאו בְּהוֹרָיוֹתָיו"- סֵפֶר שֶׁבּוּלֵי הַלֶּקֶט הִלְכוֹת שְׂמָחוֹת סִימָן יג, וְכֵן:"אָדָם אֶחָד שֶׁאֵין אַתָּה מַכִּירוֹ יוֹשֵׁב עִמָּנוּ כָּאן,אָדָם כָּשֵׁר בְּתַכְלִית, הֵן שֶׁלּוֹ הֵן וְלָאו שֶׁלּוֹ לָאו, אֵינוֹ חָכָם הַרְבֵּה, כְּרֹב חֲסִידֵי אַשְׁכְּנַז שֶׁיִּרְאָתָם קוֹדֶמֶת לְחָכְמָתָם, אֲבָל עַל כָּל דִּבּוּר וְדִבּוּר שֶׁמּוֹצִיא מִפִּיו אַתָּה יָכוֹל לִבְנוֹת חוֹמָה"- עַגְנוֹן/ עַד הֵנָּה, 116)