User blog comment:Tommy,Klaus&Kol2012+/A theory about the empty guardian/@comment-31057575-20181213193152/@comment-3045936-20181213225213

I have said that. As in season 6 in a flashback when Lucifer killed Cas. It is shown Cas being rebuilt from the destruction of his body. Also it’s hard to explain a detailed history with something that might have existed since forever.