I liked that Sam had regained a little hopefulness in 5.3 - which was obviously duly shattered by Lucifer's appearance - but I was also thinking that he's got to be thinking that if it was God who saved him from the convent and cleansed him of the demon blood so he wouldn't go through withdrawal again then it stands to reason that there's so measure of forgiveness out there for him, even if he can't forgive himself just yet.