I review a fair amount of resumes and I wouldn’t give it a second thought if I saw that. I’d probably assume it was a religious requirement of some sort before I even considered other possibilities.

As someone who reviews a lot of candidates, I would appreciate it if someone was to tell me up front whether or not they are interested in the kind of work I am offering.

I think this is a good thing. I'll take honesty and transparency over perceived flexibility any day.