פירוש על דברים 32:8

בהנחל עליון גוים WHEN THE MOST HIGH DIVIDED TO THE NATIONS THEIR INHERITANCE — when the Holy One, blessed be He gave those who provoked Him to anger their inheritance, He afterwards caused the flood to pass over them and He drowned them (Sifrei Devarim 311:1)

יצב גבולות עמים, after the tower of Babylon episode, when mankind had lived in a single community, G’d separated them, dividing them up, and established territorial boundaries for the various new nations. Instead of destroying the people who had engaged in building the tower as a challenge to G’d, He did not destroy them as He had the generation of the deluge, but limited their future scope of influence, by assigning only clearly marked territories within which they could be sovereign.

בהנחל עליון גוים, "When the Supreme One gave nations their inheritance, etc." This is a reference to the time when G'd assigned "guardian angels" for the various Gentile nations to represent them at the celestial court. This is an allusion to the fact that G'd considered these nations as inferior so that He did not want to relate to them directly but only by means of an intermediary.