The word, להבדיל, “to separate,” is found only five times in all of Tanach. It appeared twice in Parshat Shemini.
The Book of Bereishit spoke of separating between light and darkness and day and night. The separation mentioned in שמיני as well as in Yechezkel, speaks of a separation between holy and profane. The final separation is between טמא וטהור, the pure and the impure.
The role of the Jewish people was to remain separate in order to achieve holiness. They needed to make a concerted effort to remove themselves from the impure and the profane. The vehicle to achieve this holiness was through the observance of the 613 Mitzvot.
Years ago, we were privileged to have an American Noachide couple, address our students at Machon Meir. They told the students the following: “Our job through the observance of the Seven Noachide Laws, allows us to become righteous. Your job, as Jews, is to become holy.”
This was a profound message, as it summed up the concept of “righteous Gentiles,” and “holy Jews.” ( I later learned that this couple ultimately converted and made Aliya.)
The point here is that everything in this world has its specific purpose. This is why it is forbidden to mix different fruit trees, or crossbreed animals.
We define our role when we recite the Havdalah prayer every Saturday night. Shabbat is a separation between holy and profane, and we mention אור לחושך, light to darkness, and Israel and the nations.
Perhaps the world would be a better place if these defined roles were followed. Each individual would know his place, and everyone would achieve their maximum.