I guess one road we could go down would be...
You: What is your positive evidence for being an atheist?
Me: You mean what is my positive evidence for not believing in a Christian, or indeed Abrahamic god?
You: Yes. [I'd imagine this is what you'd say, but could be wrong]
Me: Same as yours for not believing in Odin - you haven't seen any evidence that Odin exists, so you don't.
You: Ah, but I have positive evidence of my beliefs - Jesus lives etc.. (perhaps what you think?)
Me: But that's what everyone says. That's what people who believe in any god would say. They've been touched by Vishnu, or whatever. I guess what this comes down to what you'd call admissable evidence. If a warm squishy feeling inside is evidence of one god's existence to some people, and another god to some others, then maybe its not really very compelling evidence of anything at all.
You: Oh, I see. Gosh, never thought about it that way. Maybe there isn't such a thing as a Christian God after all. Maybe there aren't
any gods. Oh, and I like the term Abrahamic too, that's great. (probably putting words in your mouth).