I haven't really "argued" with them, or said anything back. I usually just say, "I'm not arguing with you about this," or something. The only time I really said anything back went like this:
Cori: So, you're an Atheist now?
Me: Yeah, I'm a Gnostic Atheist.
Cori: What made you decide to do that?
Me: I don't believe in God. Any God. Not yours, not any other religion's.
Cori: How do you think the universe got here? It's an amazing thing.
Me: I'm not going to argue this. I respect you and I respect Christianity.
Cori: So...what if you're wrong?
Me: What if you're wrong?
Cori: I'm not.
Me: Exactly. You won't even consider the possibility that you're wrong.
As you can well imagine; the point I made ticked him off. He proceeded to walk away, and ignore me for the continuation of the day.
Cori: So, you're an Atheist now?
Me: Yeah, I'm a Gnostic Atheist.
Cori: What made you decide to do that?
Me: I don't believe in God. Any God. Not yours, not any other religion's.
Cori: How do you think the universe got here? It's an amazing thing.
Me: I'm not going to argue this. I respect you and I respect Christianity.
Cori: So...what if you're wrong?
Me: What if you're wrong?
Cori: I'm not.
Me: Exactly. You won't even consider the possibility that you're wrong.
As you can well imagine; the point I made ticked him off. He proceeded to walk away, and ignore me for the continuation of the day.
"On the first day, man created God." - Anonymous