Well, he is family. Slightly psychotic family, but I'd like to think it counts for something. I'm not saying he wouldn't want anything in return, but you need to be gotten out of there.

[And if Lucifer's willing to do it, then that's great, because Gabriel hasn't got the balls to mess with Heaven.]

Depends on what he'd want, of course, but whatever awful thing he'd want you to do, ten bucks says he could just do it himself. It's worth at least listening to what he has to say.