וְדִרְשׁ֞וּ אֶת־שְׁל֣וֹם הָעִ֗יר אֲשֶׁ֨ר הִגְלֵ֤יתִי אֶתְכֶם֙ שָׁ֔מָּה וְהִתְפַּֽלְל֥וּ בַעֲדָ֖הּ אֶל־יְהוָ֑ה כִּ֣י בִשְׁלוֹמָ֔הּ יִהְיֶ֥ה לָכֶ֖ם שָׁלֽוֹם׃ (פ)
E procurai a paz da cidade, para a qual fiz que fôsseis levados cativos, e orai por ela ao SENHOR: porque na sua paz vós tereis paz.
Shabbat Siddur Sefard Linear
The custom to pray for the welfare of the government is mentioned in Kol Bo and Avudraham. The latter writes, “After the reading of the Torah, it is customary to bless the king and pray to God that he be given might and power over his enemies. This prayer is based on Jeremiah 29:7, “Seek the peace of the city where I have sent you into exile, and pray to Adonoy in its behalf; for in its peace, you will have peace.” We also find reference to such prayer in the Mishna, (Maseches Avos 3:2), “Rabbi Chanina, Deputy Kohein Gadol, says: Pray for the welfare of the government, because if people had no fear of it, they would swallow each other alive.”