Let me tell you why God made the world.
One afternoon, before anything was made, God the Father, God the Son, and God the Holy Spirit sat around in the unity of their Godhead discussing one of the Father's fixations. From all eternity, it seems, he had had this thing about being. He would keep thinking up all kinds of unnecessary things - new ways of being and new kinds of beings to be. And as they talked, God the Son suddenly said, "Really, this is absolutely great stuff Why don't 1 go out and mix us up a batch?" And God the Holy Spirit said, "Terrific! I'll help you." So they all pitched in, and after supper that night, the Son and the Holy Spirit put on this tremendous show of being for the Father. It was full of water and light and frogs; pine cones kept dropping all over the place, and crazy fish swam around in the wineglasses. There were mushrooms and mastodons, grapes and geese, tornadoes and tigers - and men and women everywhere to taste them, to juggle them, to join them, and to love them. And God the Father looked at the whole wild party and said, "Wonderful! just what I had in mind! Tov! Tov! Tov!" And all God the Son and God the Holy Spirit could think of to say was the same thing: "Tov! Tov! Tov!" So they shouted together "Tov meod!" and they laughed for ages and ages, saying things like how great it was for beings to be, and how clever of the Father to think of the idea, and how kind of the Son to go to all that trouble putting it together, and how considerate of the Spirit to spend so much time directing and choreographing And for ever and ever they told old jokes, and the Father and the son drank their wine in unitate Spiritus Sancti, and they all threw ripe olives and pickled mushrooms at each other per omnia saecula saeculorum, Amen.
It is, I grant you, a crass analogy; but crass analogies are the safest. Everybody knows that God is not three old men throwing olives at each other. Not everyone, I'm afraid, is equally clear that God is not a cosmic force or a principle of being or any other dish of celestial blancmange we might choose to call him. Accordingly, I give you the central truth that creation is the result of a trinitarian bash, and leave the details of the analogy to sort themselves out as best they can.