It was AKA: I’ve had 17 years to think about this and have a lot of feelings.
I’ve been seeing a lot of posts/fics that have everyone’s favorite bookstore angel as the one who is soft and sweet down to his core, and I don’t think that’s true. As others have pointed out, he’s the one willing to (and almost did!) shoot Adam, he allows a man to be guillotined in his place and doesn’t make a move to save him. He’s got a flaming sword and he knows how to use it. What I think gets overlooked often is that Aziraphale doesn’t really love Humans.
Aziraphale steeps himself in human comfort and pleasure: cocoa, fussy bow ties, books, and especially food.
In other words, he likes human THINGS, but he doesn’t seem to have much fond feeling for humans themselves. Oh, sure, he loves them in the same way angels love all God’s creation, but that’s more of a background hum of love, not an active thing. He likes specific humans, like Shakespeare. But he has a very similar emotional distance from Humanity as the other angels we see do.
In fact, his Soft Academic persona is specifically chosen to maintain that distance. An absent-minded rare bookseller may seem like a marshmallow of a person, but there’s an air of disinterest involved. People can be fond of him, but they know better than to try to get close to him while his mind is on some lofty, learned pursuit. Even his bookshop hours are basically a riddle to keep people away.
Contrast that with A. J. Crowley, who nurtures living things (in his own special shouty way), who balks at killing the child Antichrist, whose idea of evil is messing up mobile networks. He loves the things humans create, but he loves them for the ingenuity and passion put into making them. When he questions the Ineffable Plan, it centers on what it’s doing to people: why are You making them suffer, why are You drowning them, why do You test them to destruction?
That last question doesn’t feel like a new thought for Crowley. Maybe he’s asked versions of it over and over again, maybe even right to the Almighty’s face before he fell. He was cast out of Heaven for asking questions, and my money’s on those being the questions.
Crowley’s persona is Cool Untouchable Rock God. It’s the kind of thing that intrigues humans and draws them closer.
To sum up, Crowley pretends to be invulnerable and distant because he is so, so emotionally the opposite. Aziraphale pretends to be all squishy because he isn’t, really. Except, of course, when they come together and balance each other out.
