Aziraphale ducked down a bit, trying to get a better look at the man. "Are you sure? You're all red in the face." He smiled wryly. "I really was trying to make sure you were all right, you know, not trying to kill you."

As he spoke, he briefly considered what that must have been like. He was still getting used to the idea of breathing. Last night he had briefly forgotten he was doing it, only to find that his body had entirely taken over. It was automatic. So when it went wrong it had to be truly terrifying.