I believe in Creationism (God created the universe). My reasoning is this: if God did not create the universe, then the universe came to be out of nothing, all of existence is finite, and at some point will eventually come to an end. If God did not create the universe, then the knowable universe is all there is, no more.
This could not be true, however, because the nature of existence has a number of infinite qualities which demand that the knowable universe is suspended in a state of infinity and was in-fact created by an infinite God. There is, for instance, the fact that it infinitely the present moment, it is never the past or the future. We know by experience that people who think of the past or the future in concrete terms are a bit foolish, because the past cannot be changed and the future not predicted, and these people usually end up face to face with their assumptions otherwise. I wouldn't feel too bad, though, even Einstein thought space and time were unified.
If it weren't infitely the present, then time would be unified to space (as we now know is incorrect in terms of quantum theory), and time would have begun at the same time space did, as well as end when space will end. However, we know this is not the case by the simplest means of our human consciousness and how we experience existing. It's perpetual. It is not broken up in finite chunks. Even though you are a year older on your birthday, you'll feel as you did one moment ago. We do break things down in a finite fashion, but if you were to break down the passage of time into smaller and smaller and smaller events, you'd never reach a point where the human consciousness differentiated in a segmented fashion. Considering that, why do we measure time? Because this correlates to the changes and developments in the physical world, like the aging process, seasons, etc.
The thing is, if you were to expand these changes and developments larger and larger, as you did time segmentation smaller and smaller, you'd likewise never reach an endpoint that was finitely segmented. This is because there isn't one. The finite, known universe is suspended and sustained in an eternal realm, by an eternal God (the "heavenly realm"). We, as beings, are created in the image of God and are designed for an eternal existence, which is why we experience time this way despite the fact that we segment time by finite alternations in the finite realm.
How do we measure time? It's intangible. Yet, we believe it's measurable so we use the observable changes and determine that time passes, and so it came to pass, and will eventually all pass away. This is not true, because it will always be right now. The only thing that will change is that the finite will pass and the infinite will come, the perishable will perish and the imperishable will come and remain forever.