what are we supposed to say again when christians ask us where we get our morality?

[Chad32]

Somethings are universally bad, like killing people. As a social species, we need each other to live healthy lives. People who go around killing others will find themselves ostracized, regardless of what culture they come from. Though exceptions can be made, depending on the circumstances. Killing an outsider is not considered as bad as killing a family member. Even the bible says that sometimes it's ok to end someone's life sometimes.