Aziraphale figured that Gabriel wouldn't have said that had Gabriel not thought Aziraphale did, in fact, have something to say. He resisted his own sigh of disapproval before saying quite politely, "I apologize for interrupting your, ah, show-and-tell. If you'll excuse me...?" He turned to leave.

No need to drag this out more than strictly necessary. It was difficult to avoid the pseudo-Norse god when one walked out and stood next to him, after all.