Dean and Castiel in “Unfinished Business”

Dean

I don't believe a word that's coming out of your mouth.

Castiel

I thought you said that we were like family. Well, I think that too. Shouldn't trust run both ways?

Dean

Cas, I just can't.

Castiel

Dean, I do everything that you ask. I always come when you call. And I am your friend, still, despite your lack of faith in me, and now your threats. I just saved you, yet again. Has anyone but your closest kin ever done more for you? All I ask is this one thing.

Dean

Trust your plan to pop Purgatory?

Castiel

I've earned that Dean.