Do any of you still call a "first name" your Christian name?

I find it interesting, since a significant amount of people in this world are not Christians. My own name is Celtic in origin, and has no Biblical relevance whatsoever.

I know some claim this has to do with the first name one is given during baptism, but usually that is how many people acquire their middle names. I received my first name before I was baptized (I used to be Catholic).