Whether you're atheist or not doesn't really matter.
It mattered in the context that you were joking that my moral compass is based entirely on a very old book of fiction. :P
Is it wrong to make a false statement?
Yes. It is literally wrong.
We can debate semantics (or religion) if you want, but this is not the best venue.
Also, no one is entitled to their opinion. Opinions should be justifiable. Stonewalling doesn't grant you any special privilege.
Person A and Person B might have very similar moral standards but dig deep enough and you'll inevitably find difference.
I would argue the inverse.
Anyway, if you're done "poking fun"...