No that's not what makes something canon. If that were the case, the Old Gods would be more powerful than Sargeras, yet the Aspects together could beat them. because someone said that.
Anduin Identifies as a Priest, that's Anduin's own opinion of himself, however Anduin doesn't fit the criteria of a priest in warcraft anymore, he's now fits the criteria of a Paladin. And I'm not talking about him joining the KNights of the Silverhand or something like that, but that fact that he's a plate wearer, wielding a twohand sword, using melee light abilities and such. The Zandalari Prelates are elite followers of Rezan, they use plate armor, two handed weapons and wield the light through worship of Rezan. If they're Paladins, then so is Anduin.
This for @
jackofwind too
If you knew how the first Paladins came about, this wouldn't even be a debate anymore, they were priests who took up arms and fought with plate and two handed weapons... Anduin is a priest who took up wearing plate and wielding a two handed weapon into combat...
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at the 15 second mark it talks about what her pursued as a teen, does not state that he is a priest now. They even follow it up wit him that "Fate was not done with him, YEARS LATER" and "Taking up the crown, Anduin has learned that peace must be fought for" as he puts on a plate helm.
Sorry but unless there was other statements, this says nothing but that in the beginning he was a priest, which no one argues with. Most paladins started off as priests and transitioned into paladins, during times of war just like... anduin
Also anything said in HotS or done in HotS, as far as I'm aware... isn't canon to Warcraft.