Illuminations is about the creation and history of the earth and everything in it. It does begin with a big bang, but there are no voices that come over to state that this is not an act of God.
It really can be interpreted to be religious or scientific. There is a 'scene' that shows the beginning of the human race, but there's nothing that says whether the feet shown come from Adam or someone who evolved from an ape.
Illuminations is a fantastic experience. Nobody should miss it, and it's a shame that so many people don't 'get' it. "ooh, pretty" they say. I have to shake my head.
There you are in the World Showcase, in the middle of all these replicas of the countries, and in the middle of all these people - tourists and cast members - who are all speaking different languages, and you are shown a presentation of the history of the world in lights, fireworks, lasers, fire, and water. It is very moving. You get a sense of "we're all in this together" - a sense of the world coming together for a common purpose of making the world a better place to live in, with a common history and themes that bind us all together.
It really is extraordinary, and if it doesn't touch your heart, you're pretty much either stupid, or emotionally dead.