Second Centurion

I'm thinking about writing another story about on of the centurions of the Bible. This one would be about the centurion who oversaw the crucifixion and may have been the very first post-death conversion to Christianity. The line that won't stop running through my head is one that would come from him: "There's not many men who can say they killed the Son of God. In fact, there's only one... Me." I think this would come as some sort of confession towards the end of the story. My problem in plotting this thing is that I don't really want to write another Passion of the Christ and that's kind of hard to avoid since it is the central event in this character's arc. I'm still puzzling this one through.