Supernatural2005

Castiel:
You must understand why I can't intercede. Prophets are very special, they're protected.

Dean Winchester:
I get that.

Castiel:
If anything threatens a prophet, anything at all, an archangel will appear to destroy that threat. Archangels are fierce, they're absolute, they're heaven's most terrifying weapon.

Dean Winchester:
And these archangels, they're tied to prophets?

Castiel:
Yes.

Dean Winchester:
So if a prophet was in the same room as a demon...?

Castiel:
Then the most fearsome wrath of heaven would rain down on that demon. [giving a knowing look] Just so you understand why I can't help.

Dean Winchester:
Thanks, Cas.

Castiel:
Good luck.