When the nation of Israel attains the level of being a chariot for the Divine Presence, the entire world will undergo a transformation.
The patriarchs on their own were unable to effectuate this cosmic transformation because, despite their greatness, they were only individual people.
The Jewish nation, by contrast, constitutes a totality representative of the entire world, and so the effects of a qualitative transformation within the Jewish people are felt by the rest of creation, generating a global change as well.
In a certain sense, the Jewish people are the nucleus and heart of the world.
Their transformation into a state of holiness reestablishes the cosmic coordinates.
From that point forward, the entire world operates within a new framework, one in which all elements interrelate the way they were meant to, thus serving as a grand vessel for divine revelation.
Rabbi Adin Steinsaltz