"As the days of a tree are the days of my people" (Isaiah 65:22).
The great totality of Jewish history can be seen as a mighty tree, whose roots reach down to the founding fathers of our nation and whose topmost branches extend to the end of days.
The prophet's comparison of Jewish history to a great tree carries many meanings.
On the one hand, it expresses the idea that the whole of our history is a singular essence—that all its components, from the ancient past to the horizons of the future, are interconnected and integrated.
On the other hand, just as a tree branches off in different directions, so is Jewish history comprised of various era and periods, each with its distinct pathway and significance, even as they all complete and fulfill each other to form the great totality of the "tree."
–Rabbi Adin Steinsaltz
From "A New Epoch in Torah Learning," an essay by Rabbi Adin Steinsaltz