הַגִּ֤ידוּ בְמִצְרַ֙יִם֙ וְהַשְׁמִ֣יעוּ בְמִגְדּ֔וֹל וְהַשְׁמִ֥יעוּ בְנֹ֖ף וּבְתַחְפַּנְחֵ֑ס אִמְר֗וּ הִתְיַצֵּב֙ וְהָכֵ֣ן לָ֔ךְ כִּֽי־אָכְלָ֥ה חֶ֖רֶב סְבִיבֶֽיךָ׃
Declare ye in Egypt, and announce in Migdol, And announce in Noph and in Tahpanhes; Say ye: ‘Stand forth, and prepare thee, For the sword hath devoured round about thee.’
Rashi on Jeremiah
“Stand fast and prepare yourself” for the war. והכן means “and prepare.”