Why does the argument for a first cause of the universe conveniently stop with God? Where did God come from?
I was asked once by an atheist, “Why does the argument for a first cause of the universe conveniently stop with God? Where did God come from?”
When thinking through this question, it’s important to note that an infinite regress of causes is logically impossible. That is, there could not have been an infinite number of events happening one after another in our universe's past because we never would have reached the events happening now. There was a beginning.
If time and space came into existence (as physics, philosophy, and theology all indicate*), this means, by necessity, there was a first cause beginning the existence and subsequent chain of events in this universe. Since nothing caused that first cause (by definition), we can know two things about it:
The first cause had to have begun this universe by a decision of will. We know this because the first event was not a natural result of an earlier event (since there were no earlier events), and only a personal being can will to initiate something that's not an automatic result of an earlier chain of impersonal causes.
To illustrate why a personal being with a will is necessary to begin a chain of events, imagine you're watching a row of dominoes in a room where nothing else exists. Once that first domino falls, the falling of each domino can be explained by the previous domino that hit it.
But if nothing besides you exists in that room, how will the first domino fall? There is no natural force compelling it to fall—no earthquakes, no falling objects, no wind to knock over another object that would then cause it to fall. Nothing. You could watch it for all of eternity, and nothing would ever happen.
The only way those dominoes will begin to fall is if you decide on your own, expressing your own will and not physically compelled by any nonexistent prior event, to begin the chain of events by knocking over the first domino. The only way an unchanging state can change is if an agent with a will chooses to step in and begin the process.
The being who acted as the first cause of everything in existence must be a self-existent being that did not come into existence (or else that being would not be the first cause). That being is God. By definition, as the first cause, He does not have a cause.
If you ask, “Who created God?” you're really just asking, “Who is the real God—the true first, self-existent, personal cause?” because the one true God—the initiator of everything—does not, and could not, have a cause.
*I make this statement based on the actual evidence we currently have available. There are some scientists who speculate about how the universe may have eternally existed, or how it might have come into existence out of nothing. Based on the positive evidence, however, these speculations are nowhere near the best explanation. Rather, they are supported primarily by the presupposition that a naturalistic explanation must be true. What follows for many scientists is the belief that any natural explanation, no matter how unlikely and/or counter to current scientific observations (e.g., spontaneous generation—that is, things suddenly appearing out of nothing), is preferable to an explanation from outside nature.