Atheists are always being accused of being arrogant by the religious. This is my common counter, which is usually effective:
Let me get this straight. You think the Creator of the Universe cares personally about your life, and that you know, with absolute certainty, what he wants for all of humankind.
I, on the other hand, think we’re alone, likely to be cosmically average, and are basically fumbling cluelessly through our random existence trying to do the best we can.
And I’m the arrogant one?