Once Aziraphale was far enough away from Gabriel, he started walking. After all, he had no real idea where Barnaby was, so what good would running do? Besides, he hadn't gotten to see as much of the grounds as he would have liked, so a nice stroll seemed like a good idea for such a comfortable day. But Aziraphale had once, long ago, made a "pact" of sorts with a demon to stop competition between them, which is a good indicator of how little Aziraphale cared about such silly things.

Hopefully Barnaby wouldn't shoot him in the arse. ... Again.