Was Sam Being Tested Or Was Dean By The Angels?

I wonder if Sam was being tested all along by the angels, to find out what he was capable of. In "It's The Great Pumpkin, Sam Winchester" you wonder if Castiel and Uriel didn't set that up to find out what Sam was capable of and to see if he'd be able to send Samhain back to hell. I don't think Castiel or Uriel were serious about destroying the town and I don't think they were testing Dean. Or if they were testing Dean, it was to see what he'd do, when Sam used his powers. Also in "On The Head Of A Pin", who knows if that was all set up? That could've have been a test to see what Sam would do. It seems that Castiel is pretty strong, so why did he act so weak in the episode. Maybe he knew that Sam was going to come and that was part of the test to see what Sam was going to do and if he could send Alistair back to hell. Castiel seemed surprised by what Sam could do, but he wasn't afraid or he wouldn't have gone to the hospital to talk to Sam. Look at "The Monster At The End Of This Book" and that seemed like another test for Sam and how he'd react to Lilith's offer. I've just been thinking about this and wondering if the angels were testing Sam. Like I've said before, maybe it's Sam that has to send Lucifer back to hell and will he be able to do it and does Zachariah and the other angels even want Lucifer back in hell. Maybe by Sam drinking the demon blood and opening the last seal, he'll be too afraid to use his abilities because he'll think they're evil or be scared of what Dean will think of him. Maybe that's what Zach wanted all along. Sam won't have the strength or Dean to help him. Who knows?