Are You A Muslim?

A co-worker passed me in the hall this week and said, "I see you have a new Qur'an book out. Are you a Muslim?" I hesitated, smiled and said, "You wouldn't believe how many times I get asked that question." Not wishing to pursue the matter any further at that point, I quickly moved on.
Looking back over the past several years, the question usually arises when I am teaching courses on Islam or the Qur'an, when I am giving public lectures on these topics, and when I am being interviewed about my books. Both Muslims and non-Muslims have asked. My answer is always the same: "I don't answer that question, because I do not want to introduce any sort of bias into the reception of me or my ideas." I do however wonder at the motivation for asking.
While I'm sure that some people are merely curious, as if to say, "Robert Campbell doesn't sound like a Muslim name," I also suspect that others are looking to determine by what authority I speak about the Qur'an, thereby establishing how much credence they should place in what I have to say and to some extent allowing them to slot me into one of the convenient categories of apologist, detractor, heretic or zealot. After all, if I can be pigeonholed, the individual avoids the work of having to listen/read and think about the views that I am expressing.
One young Muslim woman told me that she and her husband had read through my first book (Reading the Qur'an in English) twice, and had spent a good amount of time discussing its content, all the while looking for clues that would help them determine my religious identity. They concluded that, while I certainly had an impressive understanding of the Qur'an, because I left some questions unanswered and appeared to advocate the questioning of some generally accepted precepts, I was not a Muslim. From my perspective, I was ecstatic. I had managed to get two people to carefully read through what I had to say, discuss it at length and draw some conclusions about their understanding of what it meant to be a Muslim. What more could I want?