אֶת־עַ֥ם נוֹעָ֖ז לֹ֣א תִרְאֶ֑ה עַ֣ם עִמְקֵ֤י שָׂפָה֙ מִשְּׁמ֔וֹעַ נִלְעַ֥ג לָשׁ֖וֹן אֵ֥ין בִּינָֽה׃
Thou shalt not see the fierce people; A people of a deep speech that thou canst not perceive, Of a stammering tongue that thou canst not understand.
Read halakhic rulings (Jewish law) on Isaiah 33:19: and classical halakhic sources.