Atheists love to say that, and that's how they will accept the antichrist. The antichrist will do some witchcraft magic, and the atheists will suddenly believe in God. I'm pretty sure that it's said in the Bible that the antichrist will deceive the world through miracles, so called, of course. The atheists will see their "evidence" of God (or, at least, just the supernatural), and accept the antichrist and believe that he is God.