[video]
[He pauses for a moment, unsure just how much he should say, but at the same time, not caring too much. He's not a member of the Order. He doesn't have to protect their secrets. And Sam is part of Castiel's family, so it's not like strange things are all that strange to him.]
It keeps me alive. I can't die as long as it works. The Order didn't want w-me to die too soon, I guess. [he tries to make it sound nonchalant]