“When you approach a city to wage war against it, you shall call to it for peace” (Deuteronomy 20:10). “When you approach a city” – halakha: These are the laws that were instituted in order to adhere to the ways of peace. This is what the Sages taught: These are the laws that they instituted in order to adhere to the ways of peace: A priest reads [from the Torah] first, and after him a Levite, and after him an Israelite.
See how great the power of peace is. Rabbi Yoḥanan said: The sun has never seen the dark part of the moon’s crescent.20It is always the luminous part of the lunar crescent that faces the sun. Why is it so? It is in order to adhere to the ways of peace,21It is to prevent the moon from being embarrassed, as it were, by the sun. as it is stated: “Dominion and fear are with Him; He makes peace in His heights” (Job 25:2).22God arranges even the heavenly bodies in a manner that ensures peace among them, as it were.
Rabbi Levi said: None of the constellations that move in the firmament see the one that precedes it, but only what is after it, like a person climbing down a ladder, and he turns his face [over his shoulder, to look] behind him, so that each and every constellation should say: ‘I am the first one.’ That is, “He makes peace in His heights.” Another matter, “He makes peace in His heights” – Reish Lakish said: Mikhael is all snow and Gabriel is all fire and yet they stand adjacent to one another and they do not harm one another.
Bar Kappara said: If the supernal beings, among whom there is neither jealousy, nor hatred, nor rivalry, are in need of peace, earthly beings, who consist entirely of hatred, rivalry, and jealousy, all the more so are in need of peace. The Rabbis say: You may know how great the power of peace is – even regarding war, into which a person enters only with swords and spears, the Holy One blessed be He said that when you go to wage war, begin only with peace. From where is this derived? From what we read regarding the matter: “When you approach a city….”