II.1 chapter 21

What do the words "God saw that it was good" indicate exactly?
It does not mean that God became a knowledge he did not have before he made it. For God does not have a body, such that seeing and thinking would be different, but is eternal and unchangeable, such that the past, present and future are comprehended without transition of thought.
It is instead a statement of approval for us to know it was Gods will that was why it was created. This also Plato has assigned as the most sufficient reason for the creation of the world, that good works might be made by a good God. This completes our knowledge about the creation:

• who created, was God;
• how it was created, was by the word of God
• why it was created, the will of God.

II.1 chapter 4

What does the Bible say about God and the world?
The Bible tells us that God has made the world. The prophet who said that was not a witness of those things, however; but the Wisdom of God, through which everything is made, and who is in the heart of who believes, spoke within, without sound, to the prophets of his works.

We know that there is an alternative for the theory of creation: the theory of eternal repetition of what is in the world, or one could call that eternal creation. How could an unchangeable eternal God make the world at a particular time: how can such a unique (non-repeated) change be possible, if his will never changes (as Epicurus points out)?
First, it is hard to deny that God created the world, because the world is that beautiful, that it cannot exist through something else than God, who has unutterable and invisible greatness, and is unutterable and invisible beauty too.
Second, it is anyway impossible to deny all unique (non-repeated) changes, and say every change is repeated from eternity; because then there never could be any everlasting and complete happiness (but only recurring periods of happiness and unhappiness).
We therefore believe the unchangeable and eternal God did not change his will when making the world.