כֹּ֣ה ׀ אָמַ֣ר יְהוָ֗ה אַל־יִתְהַלֵּ֤ל חָכָם֙ בְּחָכְמָת֔וֹ וְאַל־יִתְהַלֵּ֥ל הַגִּבּ֖וֹר בִּגְבֽוּרָת֑וֹ אַל־יִתְהַלֵּ֥ל עָשִׁ֖יר בְּעָשְׁרֽוֹ׃
Thus saith the LORD: Let not the wise man glory in his wisdom, neither let the mighty man glory in his might, Let not the rich man glory in his riches;
Pirkei Avot
Shammai used to say: make your [study of the] Torah a fixed practice; speak little, but do much; and receive all men with a pleasant countenance.