I know trying to untangle the mythology can be a futile effort, but I'm having trouble with something.
In season 4, Anna extracted her grace, and became entirely human (but didn't die), and from all appearances didn't suffer any ill effects. And once her grace was restored, all was well again; she seemed to have seraph-level powers (they hadn't mentioned seraphim yet, but in retrospect that's what she seemed to be...I could say something about how she seemed more powerful than Cas, a regular-tier angel at that point, but that's a rabbit hole I won't go down just yet).
In season 9, Cas stole Theo's grace to restore his first-tier angel powers. We know this because when Cas blew in the door at the bunker to rescue Metatron, and also when he blew in the doors at Randy's house to rescue Claire, we saw him tip forward as if he'd just overexerted himself (something we'd never seen before). Eventually, that grace started burning out, presumably because it wasn't Cas's, and when it ran out, Metatron said that Cas would die. The season 9 finale suggested (when Cas healed Gadreel) that every time he used his angel powers, it drained the grace he had left.
In season 10, after a recharge from Adina (courtesy of Crowley), he still didn't have wings but was a full-fledged seraph again. Problem solved, and we haven't had to worry since (so far as I know), although "not a lot but enough" from Metatron left a loose thread.
Now, fast forward to season 13. "Devil's Bargain" seemed to suggest that Lucifer was almost out of grace, and was therefore nearly human (midway through the episode he claimed he was hungry). I could accept that losing his grace would have this impact and wouldn't kill him given the events of season 4, but I didn't see him using his powers (i.e. draining his grace a la season 9's finale)...so why was it diminishing? (I get that this provided a nice little setup for the Anael story, but still.) Speaking of Anael, the same episode would have us believe that angelic grace can self-replenish, kind of like how our blood supply works (we don't know what type of angel Anael is, but whether she's a first-tier angel or a seraphim, it should be true for Cas and the archangels as well). For good measure, that was reiterated in this week's show, which reminded us that all it takes is time.
So...help me understand this. When an angel is at full power and using their own grace, there never seemed to be any limit to the power they could expend. I'm pretty sure we've seen Cas resurrect people before, so I don't understand why he couldn't have saved Sam this week (Gabriel I get, but not Cas)--after all, Gadreel did it (twice) during season 9, first in "I'm No Angel" (Castiel) and then in "Slumber Party" (Charlie). Both were done after losing his wings, and while he was supposedly recovering from The Fall. And even without his wings, Cas was able to effortlessly heal Charlie, and he appeared very menacing when they were ambushed by the government in "LOTUS."
The only time there seems to be a problem is when an angel loses some or all of their grace. I can accept that stolen grace wouldn't self-replenish. What I have an issue with is that I'd like to think the two-and-a-half seasons since Cas got his own grace back would be more than enough for it to fully replenish. I can accept that he can't teleport without wings, since they still haven't reversed Metatron's spell--but the fact that we saw Gadreel resurrect people (twice!) while at less than full power, makes me sharply question his explanation that "we weren't strong enough" to bring Sam back this week. Gabriel, yes, I get, but not Cas. And why was Lucifer running out when I didn't see him using any of his powers that I saw? He should've been able to lay low and let his grace recharge, but the implication seemed to be that he was basically human with glowing eyes at one point.
Am I making sense here?
