Castiel: When Jack was dying, I... I made a deal to save him.
Dean Winchester: You what?
Castiel: The... The price was my life. When I experienced a moment of true happiness, the Empty would be summoned and it would take me forever.
Dean Winchester: Why are you telling me this now?
Castiel: I always wondered, ever since I took that burden, that curse, I wondered what it could be, what... What my true happiness could even look like. I never found an answer. Because the one thing I want... it's something I know I can't have. But I think I know... I think I know now. Happiness isn't in the having. It's in just being. It's in just saying it.
Castiel: What, you consumed your sister?
Chuck: We came to an understanding, so spare me your contempt, Castiel, the self-hating angel of Thursday. You know what every other version of you did after "gripping him tight and raising him from perdition?" They did what they were told. But not you! Not the "one off the line with a crack in his chassis."
Castiel: My name is, um... Well, my name's not important. I do know what blind faith is. I used to just follow orders without question, and I did some pretty terrible things. I would never look beyond the plan. And then, of course, when it all came crashing down, I found myself lost. I didn't know what my purpose was anymore. And then one day, something changed, something amazing. I... I guess I found a family, and I became a father. And in that, I rediscovered my faith. I rediscovered who I am.
(Castiel is thinking about going to investigate a potential case with Jack...)
Dean Winchester: Just get out there, you know, stay busy.
Castiel: With a murder investigation?
Dean Winchester: Yeah.
Sam Winchester: Dean's not wrong. And, look, this case, uh, maybe you can help.
Dean Winchester: Alright, well, you guys go "Highway to Heaven" that b*tch.
Jack: I'll get my suit. Can we wear matching ties?
Castiel: Yeah. Blue's a good color on you.
Castiel: The Occultum is divine in its origin. It was housed for hundreds of years in an ancient temple before it was...
Dean Winchester: Plundered by pirates.
Dean Winchester: It was dug up by tomb raiders.
Dean Winchester: It was seized by the King of the Dead and his warlords. Am I close?
Castiel: Looted by invading Mongol hordes for trade on the...
Dean Winchester: Black market. Yeah, that's what... I was gonna say that next. That was the next one.
Castiel: You know, Michael, I never really liked you. Even when I was just another angel, I thought you were too haughty, too... To paraphrase a friend, you had an entire oak tree shoved up your a$$. But now? I'm looking at you, and I...I just pity you. Because you were never God's favorite. You were just a little part of his story, a tiny part of his story. You weren't even a star. At least Lucifer knew that God can't be trusted. But I guess he was always the smart one.
Rowena: What am I picking up from you two? A wee tiff? Tell your Auntie Rowena.
Dean Winchester: It's fine. Don't worry about it.
Castiel: It's fine.
Rowena: Boys? Fix it. I don't have many regrets, but the few I do still haunt me. Making Napoleon so short was just b*tchy. Telling Mick Jagger he had no future when I dumped him. And, well, everything with dear Fergus. Then one day, you die, you go to hell, they make you queen, and... you can't make it right. So fix it!