I don't remember who posted it on tumblr but there is this great meta post concerning Crowley during the holy water scene in St James Park. How nervous he is during all of it even before Aziraphale snaps at him and walks away. I'd been thinking about that recently and then saw this scene again...
(Gif by @fuckyeahgoodomens)
It's played as comedy, the whole ducks have ears. Your eye is on Crowley since he's speaking and moving around looking at the ducks.
Which is why it took me 4 months to realize how much Aziraphale's posture changes in this small frame.
Crowley, up to this point in the scene, is the rigid standing still with his cane while Aziraphale is casually feeding the ducks. Even while Crowley talks about what could happen and wanting insurance, Aziraphale continues his normal subtle movements as we are used to seeing.
As Aziraphale unfolds the paper, he still moves head bobbing, shoulders relaxed while Crowley starts discussing ducks. But then you see Aziraphale freeze for moment as he reads the words. His back straightens ever so slightly, posture hardens, seeing what's written and then his head whips to Crowley.
We know Aziraphale always does his micro movements espc when he's nervous.
But here he's completely still for a split second seeing those words and what harm they could bring to his friend.
He's upset, angry which leads to fraternizing and storming off in a very Aziraphale like huff. Lots of movements. Which to me is why the freeze speaks more volumes about his feelings about the holy water than storming off.
