What we have here is a failure to communicate.
When rationalists or humanists talk about Morality, they could be thinking of any number of specific things.
They might be thinking of how people treat each other generally. They could also be thinking of the decisions or actions we make that could have wider implications, e.g. for the environment or society.
They might be thinking of one's obligation to protect and educate the young, rather than exploit or neglect them. They could even be thinking that Morality is that same thing applied to the Aged or Disabled.
Morality is often applied to thinking about the treatment of animals. Morality could even mean the considerations for or against inter-nation conflict, economic policy, trade, or actions taken in response to human rights issues.
But when you talk to a christian about morality, they are basically thinking of one thing. To a christian, Morality means basically this:
Not touching yourself.