In this week's parashah we learn about the Mishkan, the Sanctuary that God commanded to be built to live in.
Our sages tell us that at the beginning of Creation, the Divine Presence filled the earth. Adam, the First Man, could feel God all around him.
However, seven generations followed who sinned and caused God to cease being, in revealed form, on earth. Adam, Cain, Enosh, the generation of the Flood, the generation of the Tower of Babel, the people of Sodom, and the Egyptians in the time of Abraham.
Later, seven generations of tzaddikim, righteous men, brought the Divine Presence to the earth: Abraham, Isaac, Jacob, Levi, Kohath, Amram, and Moses.
It was with the construction of the Mishkan that God returned to dwell on earth.
The function of the Jewish people is to make the world a dwelling place for God through the observance of Mitzvot and the study of Torah.
This does not mean we should bring into the world something that was never here. The original place where God was, the "garden of God," is the world. We simply need to take care of returning God to His rightful place.