Free-thinkers?

I recently had an encounter from a colleague, in which he asked me my religion. In return, I asked his. The answer that I got was - 'free-thinker'. He went on to explain what a free-thinker was, and in his words "someone who does not believe in God and religion". I was shocked, yet I played it cool.

How can someone not believe in God. Look at the things around us - the trees, the birds, the mountains, ourselves. How can coincidence give birth to all of these? There is definitely a superpower far beyond our understanding. How can one refuse to see this. It is right in front of our eyes all the time.