His wisdom exceeds his deeds
A man whose deeds are poor in comparison to his wisdom. A designation for one who knows much but whose behavior does not correspond. The opposite expression is: "His deeds exceed his wisdom."
("All his works are multiplied by his wisdom, his wisdom is established; and all his wisdom is multiplied by his works, his wisdom is not established" - Avot 3:8-9)
Translation
Expression (Hebrew)
חוכְמָתוֹ מְרֻבָּה מִמַּעֲשָׂיו
Definition (Hebrew)
אָדָם שֶׁמַּעֲשָׂיו דַּלִּים בְּהַשְׁוָאָה לְחָכְמָתוֹ. כִּנּוּי לְמִי שֶׁיּוֹדֵעַ הַרְבֵּה אַךְ הִתְנַהֲגוּתוֹ אֵינָהּ בְּהֶתְאֵם. הִפּוּכוֹ שֶׁל הַבִּטּוּי:"מַעֲשָׂיו מְרֻבִּים מֵחָכְמָתוֹ".
("כָּל שֶׁמַּעֲשָׂיו מְרֻבִּין מֵחָכְמָתוֹ חָכְמָתוֹ מִתְקַיֶּמֶת וְכָל שֶׁחָכְמָתוֹ מְרֻבָּה מִמַּעֲשָׂיו אֵין חָכְמָתוֹ מִתְקַיֶּמֶת"-אָבוֹת ג ח-ט)