Atheists cannot lead their lives in a moral or ethical way – if they did I, it would prove that I would not be required to be around and keep all of you sinners in line (and then I would be out of a job, and you don’t want that).
Here’s an example of precisely the kind of deceitful attitude that you need to watch out for:
You: “I just think it would be so sad to be a non-believer in God. How alone you must feel if you didn’t believe in an after life.”
Atheist: I appreciate your sympathy, but I can assure you it isn’t necessary. As an atheist, I find more than sufficient reason for happiness and contentment in this lifetime. There’s enough wonder and beauty in this world that I see no need for any other. On the other hand, I feel concern for you, if you’re so unhappy with this life that you’ve staked all your happiness on the existence of another. Rather than putting all your effort into wishing there’s an afterlife where your troubles will be magically resolved, I think you’d do better to strive toward making this life what you wish it to be.
You: “What prevents you from doing bad things in life? How do you determine right from wrong?”
Atheist: The same way as anyone else: we use reason to evaluate the consequences of our actions, coupled with the sense of compassion that lets us imagine what it would be like to be in the position of other people whom our actions affect. It’s not difficult. Frankly, I’d be concerned by someone who prefers to be told what to do, rather than letting their own conscience guide them. That sort of morality is far too easily turned to evil and wrongdoing.
If you hear this type of complete distortion of the facts from a Heathen, don’t listen to what they are actually saying – for that is the path that will lead you astray. Simply ignore their reason and remind them that if they keep up this kind blasphemous nonsense *I* will ensure they end up in very nasty place indeed. Like, Forever.