As a side note: Its 6 days, not 7. Day 7 (the Sabbath) was for resting.
As a longer thought: God, as a omnipotent being, obviously doesn't need to rest, and given the idea that he (for lack of a better pronoun) is essentially keeping the universe running himself, the whole concept of 'God resting' is obviously (to me, and many others) poetic. Looking at the rest of the Genesis creation story through 'poetic narrative' lenses:
From the beginning of the universe until the start of human written history, we can divide it up into Eons (non-specific but LONG periods of time):
Eon 1: - The universe was 'formless' and chaotic. - Pure energy / light and darkness / vacuum / void become separate.
Eon 2: - The planets and other 'heavenly bodies' or galaxies start to spin together into units. - Planetary atmospheres form. (The separation between 'waters below' (the unknown depths of the sea) and 'waters above' (the vast 'ocean' of space') from a ).
Eon 3: - Focussing on Earth, the planet surface began to stabilise, continents appear. - Plants and other 'basic' forms of life begin to show up and spread all over the planet.
Eon 4: - The moon shows up, the atmosphere clears up a bit, stars are now visible, the earths spin is now stable re. Day and Night.
Eon 5: - Animals! Firstly water based, then birds. Maybe huge birds (dinosaurs?) No non-bird land-dwellers yet.
Eon 6: - Land based animals, 'finally' humans showing up.
Eon 7: - Now. Beginning of written histories.
The above pattern is a pretty strict interpretation of the first chapter of Genesis, with most of the poetic stuff stripped out. It's kind of interesting how much of it does kind of map to our current understanding of the beginning of the universe and our planet.
What do you think?