"And the man went to the land of the Hittites and built a city, and called its name Luz; that is its name to this day" (Judges 1:26). It was taught in a baraita: This is the Luz in which they dye the sky-blue dye; this is the Luz against which Sennacherib came and did not throw it into confusion, and which Nebuchadnezzar came against and did not destroy; and even the Angel of Death has no permission to pass through it. Rather, the elders who are in it, when their mind becomes weary of them, go outside the wall, and there they die. And are these matters not derived through an a fortiori inference? If this Canaanite, who did not speak with his mouth and did not walk with his feet, nonetheless brought about deliverance for himself and for his descendants until the end of all generations, then one who performs an act of escort with his feet, all the more so.
The City Of Luz
Sotah 46b
״וַיֵּלֶךְ הָאִישׁ אֶרֶץ הַחִתִּים וַיִּבֶן עִיר וַיִּקְרָא שְׁמָהּ לוּז הוּא שְׁמָהּ עַד הַיּוֹם הַזֶּה״, תַּנְיָא: הִיא לוּז שֶׁצּוֹבְעִין בָּהּ תְּכֵלֶת, הִיא לוּז שֶׁבָּא סַנְחֵרִיב וְלֹא בִּלְבְּלָהּ, נְבוּכַדְנֶצַּר וְלֹא הֶחְרִיבָהּ, וְאַף מַלְאַךְ הַמָּוֶת אֵין לוֹ רְשׁוּת לַעֲבוֹר בָּהּ. אֶלָּא זְקֵנִים שֶׁבָּהּ, בִּזְמַן שֶׁדַּעְתָּן קָצָה עֲלֵיהֶן יוֹצְאִין חוּץ לַחוֹמָה, וְהֵן מֵתִים. וַהֲלֹא דְּבָרִים קַל וָחוֹמֶר: וּמָה כְּנַעֲנִי זֶה שֶׁלֹּא דִּיבֵּר בְּפִיו, וְלֹא הָלַךְ בְּרַגְלָיו — גָּרַם הַצָּלָה לוֹ וּלְזַרְעוֹ עַד סוֹף כׇּל הַדּוֹרוֹת, מִי שֶׁעוֹשֶׂה לְוָיָה בְּרַגְלָיו — עַל אַחַת כַּמָּה וְכַמָּה.