One of this week's mitzvot is called Ma'akeh (fence). When you build a house, you must put a fence around the roof so no one falls. It seems logical, doesn't it? And it is. Why do we need the Torah to tell us something we would have thought of anyway?
One of the answers is that God created the world in such a way that things happen according to certain rules that we call Nature.
The Jewish people transcend nature (both in space and time). Given this, how can it be that a Jew builds a house and someone has an accident and falls from the roof? God should protect the Jew and "reveal" how he truly transcends nature by preventing people from falling from the roof of his house. In other words, there should be a miracle that prevents people from falling from the roofs of Jewish houses!
But no. We don't rely on miracles. God requires, through His Mitzvot, that we "play" according to the rules of nature and, for example, put a fence on the roof of a house so that no one falls.
One application of this idea is that, while the Jewish people are eternal, it is up to us to reveal that continuity in a practical way. We transcend nature, but if we do not actively live Judaism, if we marry within our own communities, if we do not raise our children in Judaism at home, this transcendence remains hidden. We must imbue the material world with our spiritual transcendence.