The fact that God created the world is a fundamental principle of our religion. God is the Almighty Creator who is in charge of world and command us to do mitzvos. In addition, Rashi mentions how it is relevant so we know why the Jews have a right to their homeland, Eretz Yisrael.
Why did the Torah spell out so much more about history afterwards?
Rambam explains the general lessons learned from Bereishis show that there is reward and punishment, so if people sin, they can be punished or exiled. Thus, when the cannanites has sinned for so many generations, they were punished, and the Jews took over their land, where they must keep the mitzvos or they too could face exile.
But why did it need to go through the 6 days of creation? Why can’t the Torah just say God created the world and move on?
The Mishnah in Avos (5:1) discusses a related question – Why did God need to create the world in so many steps:
With ten ma’amoros (utterances) the world was created. And what does this teach us? Couldn’t the world have been created with one ma’amar? Rather to take retribution from the reshaim who destroy the world that was created with ten ma’amoros and to give reward to the tzadikim who sustain the world that was created with ten ma’amoros.
The Mishnah is saying man’s actions matter because God put more “effort” into creating the world. He did not just create it in one instant and that was it, but remained involved in it. This Divine involvement in the universe shows that the universe is important, and that the actions man does have consequences. This fits with the theme of reward and punishment in Bereishis that the Ramban mentions.
There is also another significance to the 6 days and the 10 maamaros. If the universe had been created in one instant, everything would be independent of everything else, and man would just be one of the creations. But because the universe was created in a process of “6 days”, everything leads up to man, he is the purpose of all of creation. Man’s actions will determine whether the creation of the universe was justified. This idea is seen in the pesukim in bereishis. On the 6th day man is created, and God tells him that he is to rule over the rest of nature that was created before him. He is the purpose of creation and responsible for everything. (See R.S. Hirsh on Avos for a similar approach.)
Summary
Q: So why does the Torah spell out the details of Bereishis? More fundamentally, why did God “take 6 days” and “10 maamaros” to create the universe, instead of creating it in one instant or with one ma’amar?
A: The process of “6 days of creation” demonstrated how man was the purpose of creation and is responsible for the whole universe. The 10 maamaros showed that the universe matters, and that God is involved in it and cares about it. Therefore man is responsible to listen to God and sustain the world, not disobey and destroy the world…
