In Fantastic Beasts 3, Dumbledore asks Newt, a Magizoologist, to lead a team of wizards, witches, and a Muggle baker on a dangerous mission to stop the dark wizard Gellert Grindelwald from seizing control of the wizarding world. Because of this, The Rowling Library theorises that Dumbledore gives Jacob the wand so everyone will think he's a wizard throughout their quest.
"It is clear Dumbledore has a plan (or even more than one) in this movie and making Jacob look like a Wizard could be one of them," stated the theory. "That may also be the explanation for why he is eating at the Great Hall in Hogwarts. If Dumbledore wants to everyone believe he is a wizard, why wouldn't he be in Hogwarts behaving like everyone else?" After all, he's shown waving a wand around — so maybe he's trying to look like a real wizard?
The only problem is, how could a muggle be allowed inside Hogwarts when it's covered in a protective charm? The Rowling Library believes Jacob can bypass the charm since he was invited in, much like Moaning Myrtle's parents were invited to see her daughter's body when she died, which was revealed in Harry Potter and the Chamber of Secrets.
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