They would draw their power from Rezan, but now he’s kicked the bucket, probably the cat one who’s name escapes me.
They also don’t use “The Light” like Humans/Dwarfs/Draenei/Belves use it.
It’s more of a Sunwalker-esk type of paladin. Not really a paladin, but we don’t want another class which is basically a paladin.
Rezan was Loa of authority, light and Zandalar rulers. Quite fitting for Prelate.
(My Prelate would get power from faith in Rezan, but will continue his job in carrying other Loa’s will).
Shadra the venom queen was giving both light and shadow abilities to her high priestess.
Shirvallah’s follower was using heal that was light-based. (talking about Vanilla add during High priest Thekal encounter).
Apparently Lokou is also canon now according to Ty’Jin’s follower traits. In RPG book she was able to channel light powers too but we cannot be sure now how it exactly transferred to WoW.
Light-wielders acquire their ability to wield the Light through their faith and their willpower. They can acquire this degree of faith and willpower through a number of different methods, such as the Three Virtues system of the Church of the Holy Light, or perhaps the more direct teachings of the Naaru.
Zandalari prelates of Rezan are warrior-priests who adhere to the teachings of Rezan and wield the Light.
Therefore, it makes sense to suggest that the teachings of Rezan are similar to the teachings of the Church of the Holy Light and the teachings of the Naaru, in that they bolster the faith and willpower of the prelate, to the point where they are capable of wielding the Light.
Prelates don’t directly draw their magic from Rezan themselves, as shown by the fact that some prelates are still capable of wielding the Light even after Rezan died. How? They didn’t lose the faith instilled in them by Rezan’s teachings, that’s how.