I watched the Season 4 finale, again I just love Cas in that one. I think he learns the most out of all of them in that whole scenario. So this is the first of many mini-fics I've written about the Season 4 Finale.
Sam hadn't talked to God since Dean died. These past four months he was mad. Madder 'n Hell. He was mad at God…at Dean., himself, the demons and the list went on and on.
When Dean returned Sam'd deemed himself damned and hadn't seen the point in praying anymore.
Finally standing in that convent (by the way, they were never returning to Maryland) with Ruby revealing she'd betrayed him and in her insane twisted way still loved him, he prayed. Prayed for forgiveness. For help. For Dean to forgive him and his safety. Bobby too.
Then when the two of them ended up in that plane he knew God had never given up on him, and this time? When it counted the most? He'd heard Sam loud and clear. And Sam promised to himself and God never to give up faith. Or give up on faith, or loose it.
As Sam fell into the pit he prayed, for everyone's safety. For Dean's soul to heal, and for Lucifer and Michael to reconcile, like he and Dean had.
Up, way high above Sam's ever falling head God heard his prayer and smiled.