וְהָיָ֣ה ׀ הַנִּשְׁאָ֣ר בְּצִיּ֗וֹן וְהַנּוֹתָר֙ בִּיר֣וּשָׁלִַ֔ם קָד֖וֹשׁ יֵאָ֣מֶר ל֑וֹ כָּל־הַכָּת֥וּב לַחַיִּ֖ים בִּירוּשָׁלִָֽם׃
And it shall come to pass, that he that is left in Zion, and he that remaineth in Jerusalem, shall be called holy, even every one that is written unto life in Jerusalem;
Rashi on Isaiah
And it shall come to pass, that every survivor among them will settle in Zion.
Ibn Ezra on Isaiah
That is written, etc. I shall explain this in the minor prophets (Mal. 3:16).3The words referred to are כתוב בשמים מכתב לא ימחק, What is written by God is a writing which can never be erased. It is a figurative expression for: it is quite sure, it is immutable.