Mr. Arthur Weasley: Harry, there are some within the Ministry who would strongly discourage me from divulging what I'm about to reveal to you, but I think that you need to know the facts. You are in danger. Grave danger.
Harry: Has this anything to do with Sirius Black?
Mr. Arthur Weasley: What do you know about Sirius Black, Harry?
Harry: Only that he's escaped from Azkaban.
Mr. Arthur Weasley: Do you know why? Thirteen years ago, when you stopped...
Mr. Arthur Weasley: ...don't say his name.
Mr. Arthur Weasley: When you stopped You Know Who, Black lost everything. But to this day, he still remains a faithful servant. And his mind you are the only thing that stands in the way of You-Know-Who returning to power. And that is why he has escaped from Azkaban. To find you...
Harry: And kill me.
Mr. Arthur Weasley: Harry, I want you to swear to me that whatever you might hear, you won't go looking for Black.
Harry: Mr. Weasley, why would I go looking for someone who wants to kill me?
Mr. Weasley moves about the Leaky Cauldron with Harry while conveying information to him about Black.