The current consensus among cosmologists is that with the Big-Bang, matter, space, and time came into existence. Current thought is that there was not a cold vacuum of space where one could have watched the Big-Bang occur, but rather that space came about as a result of the Big-Bang. Imagine a parking space with a car. The parking space can exist, being empty when no car occupies it. However, if the parking space does not exist, neither can the car (in that spot at least). Neither can time elapse, measuring the existence of the space or the amount of time the car occupies it.
Everything that begins to exist has a cause. Although this cannot be proven with absolute certainty, history and common sense affirm it. The only other option is that something began to exist without a cause. Although this cannot be ruled out at the outset, not only do we lack experience and knowledge that this can be the case, but it seems absurd. Ex nihilo nihil fit is the Latin for 'out of nothing, nothing comes'. Just as you cannot get blood out of a turnip, you cannot get something out of nothing. Even the famous Scottish skeptic, David Hume, wrote, "But allow me to tell you that I never asserted so absurd a Proposition as that anything might arise without a cause."

The Big-Bang actually creates a tremendous problem for the atheist. If nothing at all existed prior to the Big-Bang, then what exploded? Moreover, the atheistic view, that the universe is all there is, requires that the universe, for no reason, just came into existence out of nothing. But again, this seems absurd. If the Christian had postulated such a proposition, he or she would have been laughed out of court.
The response of atheists to this dilemma has been silence. Atheist philosopher, Quentin Smith writes:

The idea that the Big Bang theory allows us to infer that the universe began to exist about 15 billion years ago has attracted the attention of many theists. This theory seemed to confirm or at least lend support to the theological doctrine of creation ex nihilo. Indeed, the suggestion of a divine creation seemed so compelling that the notion that "God created the Big Bang" has taken a hold on popular consciousness and become a staple in the theistic component of ‘educated common sense’. By contrast, the response of atheists and agnostics to this development has been comparatively lame.
Under the atheistic worldview, the Big-Bang is problematic. It requires the atheist to make an incredible "leap of faith," a leap that goes against experience and common sense. By contrast, although some Christians have problems with the estimated age of the universe, the Big-Bang theory is at home within the Christian worldview. We observe that everything that begins to exist has a cause. The Big-Bang confirms that the universe began to exist. Therefore, the universe must have been caused.

The skeptic may respond, "If an uncaused beginning is problematic for the universe, isn’t it problematic for God as well?" Not at all. Uncaused beginnings are problematic no matter what or Who you may be talking about. However, while we now know that the universe had a beginning, no one is claiming that God began to exist.

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