Screencaptures: SPN S04E07 ‘It’s the Great Pumpkin, Sam Winchester’ HD

I mean, honestly, knowing the characters as well as I do, I would hope that if someone asked Cas to kill Sam and Dean that he would do it. I mean, just do what you’re asked! Do what you’re told. [Laughs.] I think that it would be without dramatic merit if Cas were told to do something like take out Sam and Dean and were to do it without any struggle. So I’m sure that there will be some sort of tension around any programming conflict, with Sam and Dean.