Believer says: Atheists have to accept the premise that everything came from nothing. However, everybody knows that nothing comes from nothing.
But skeptic says: Uh, you don't have to accept the premise that everything came from nothing. You can say that you don't know and still be an atheist.
Even if a theist says science can’t explain what brought the Big Bang about, the declaration doesn’t do anything to support the Bible. Science simply doesn't know yet, may never know. But it doesn't mean we must go to the Bible.