I stole the title of this article from Gregory Koukl of Stand to Reason because this phrase best explains the reality of what we see in the universe. To be a consistent atheist, you must believe in a miraculous beginning to the universe. A commitment to naturalism does not allow for divine intervention, so the universe would have to have popped into being without a cause.
Atheists recognize this problem and have proposed several models suggesting that the universe has always existed or is eternal in the past. But if the universe is static or has always existed, then how did we ever get to this point in history? How did history ever get started? We cannot count back to infinity, and if we cannot count back to the beginning, how would we ever reach the starting line?
Albert Einstein realized, when developing his theory of relativity, that the universe was not eternal; space, time, and matter all had a beginning. He later called this discovery “irritating.” In fact, he was so irritated that he introduced a fudge factor he called the cosmological constant, which would indicate the universe is actually static. Other scientists soon realized what Einstein had done and reluctantly concluded that the universe indeed was finite in the past.
The Kalam Cosmological Argument goes like this:
Premise #1: Everything that begins to exist has a cause.
Premise #2: The universe began to exist.
Conclusion: The universe has a cause.
You’ll notice that premise #1 says “everything that begins to exist,” meaning that there had to be an agent to begin the universe — the greatest conceivable, powerful, personal being: God, or “The Big Banger.”