In Harry Potter and The Prisoner Of Azkaban, Remus Lupin enters Harry's life as the mysterious new Defence Against The Dark Arts Teacher. Before long, the talented wizard is a confidant, mentor, and friend to Harry, providing him with a newfound connection to his parents. Lupin continues to be an important figure within Harry's life even after he steps down as a professor at Hogwarts.

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Lupin is intelligent, morally grounded, and level-headed; exactly the kind of wizard that many would gravitate towards for competent advice. Unfortunately, a lifetime of prejudicial mistreatment and trauma—namely as a result of being a werewolf—has also skewed his perception of the world. As a result, Lupin holds beliefs that vary greatly in their merit.

Best: "Eat. You'll Feel Better."

Lupin has Harry's best interests at heart from their very first interaction, in which he saves Harry from a Dementor. He gently exercises his authority over the 13-year-old student by advising him to eat chocolate in the wake of the attack. This advice might seem trivial, but it provides Harry with comfort after an unexpected and frightening experience that shakes him to his core. It also sets the precedent for the nurturing presence that Lupin will have in Harry's life, particularly over the coming school year.

Worst: "I Am Too Old For You, Too Poor... Too Dangerous."

Remus and Nymphadora.

The romance between Lupin and Tonks isn't really explored in the films, but this line from the books summarizes its rocky beginnings. Suffering decades of judgment as a result of his condition, Lupin believes that being a werewolf makes him unworthy and unsuitable for a lot of the things he wants. When he and Nymphadora Tonks fall for one another, he rejects his chance at happiness as a result of this deep-seated self-criticism. He tells Tonks repeatedly that he not good enough for her, and insists that she deserves someone "young and whole." Thankfully, Tonks rejects this advice and insists that they should be together, until eventually, Lupin is able to embrace her love for him.

Best: "Our Pain Becomes Their Power"

Remus advising Neville.

These words are first and foremost advice for dealing with dementors. As Harry's teacher, Lupin explains the way that dementors feed and thrive off the pain of others, and furthermore how they can be defeated when that pain is replaced with joy.

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While it is not explicitly stated, this lesson also informs the way that Harry deals with his other enemies. In his attempts to manipulate him, Voldemort targets Harry's pain, loss, and anger. Lupin's advice rings true when Harry realizes that the source of his strength lies in the love and friendships that he cultivates over his life—the happiest aspects of his existence.

Worst: "You Should Have Realised, If Voldemort Didn't Kill You, We Would"

Remus and Sirius.

When Lupin is confronted with the former friend who betrayed Lily and James Potter, he is overcome with anger and anguish. While Sirius Black is the one to utter this threat in the film, it is Lupin's line in the book—a promise to kill Peter Pettigrew. Even if his advice had been given at a time when it was actually of use, its sentiment would have meant nothing to Pettigrew. At the moment of his betrayal, it is unlikely that Pettigrew would have ever feared the threats of his closest friends over the promises of someone as vicious as Voldemort. Furthermore, as Harry points out, becoming murderers themselves would be against the wishes of Lily and James.

Best: "He And Your Mother Gave Their Lives To Save Yours. Gambling Their Sacrifice By Wandering Around The Castle Unprotected With A Killer On The Loose Seems To Be A Pretty Poor Way To Repay Them"

Lupin finds Harry walking through the castle halls at night, alone and unprotected, seemingly indifferent to the imminent threat of murder. His frustration with the reckless third-year is completely justified and warrants the brutally honest response. Used to deflecting criticism from certain staff members, Harry's unwillingness to defend himself shows that he takes what Lupin says seriously. He immediately tells Lupin what he saw on the map, and stops his impromptu search for Peter Pettigrew—deciding not to let curiosity and stubbornness get the better of him.

Worst: "Parents Will Not Want A—Well, Someone Like Me Teaching Their Children"

Lupin as a werewolf in Harry Potter.

Despite Harry's objections, Lupin resigns as Defence Against the Dark Arts teacher after just one year in the position. He explains to Harry that he made the decision after word got out of his condition.

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Lupin believed that it was only a matter of time before he would be called to resign by swarms of fearful parents and, while this may be true, his explanation gives little comfort to Harry. Lupin could have fought for his right to stay, especially as he would have had the backing of several students and staff members.

Best: "Fear Makes People Do Terrible Things"

Remus, Ron, and Harry.

In the immediate aftermath of Voldemort's return, Minister For Magic Cornelius Fudge refuses to admit the truth that so many others swear by. Overcome with fear, he shuts down any suggestion that the wizarding world could be in the same inescapable danger that it was once in. The ramifications that this has in Harry's life and beyond are enough to make anyone bitter, but Lupin advises Harry that Fudge's ignorance is not malicious. He helps Harry to understand Fudge's perspective as the protector of a world that is in the clutches of grave danger.

Worst: "You're Blinded By Hatred"

Remus, Nymphadora, Molly Weasely, and Arthur Weasely.

In Harry Potter and The Half-Blood Prince, Harry becomes certain that Snape is aiding Draco Malfoy in a villainous plot. Lupin is steadfast in his response, telling Harry to believe in Dumbledore's judgment and trust the Professor. Lupin is somewhat correct in his assessment, recognizing Harry's long-term hatred of Snape, and he is also right to trust the Potions Master. However, his advice also ignores the legitimacy of Harry's argument and pushes him even further out of reach.

Best: "It Is The Quality Of One's Convictions That Determines Success, Not The Number Of Followers"

Remus and Kingsley.

Standing side-by-side and ready to fight in the Battle Of Hogwarts, Lupin shares some words of wisdom with future Minister for Magic Kingsley Shacklebolt. His advice is for no one in particular, but rather a reminder that the battle they enter into is absolutely worthwhile and winnable, even if they are outnumbered.

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Lupin's words communicate that while the followers who stand behind Voldemort are numerous, their reasons for fighting are far less important and powerful than those held by Harry's defenders.

Worst: "Harry, I'm Sure James Would Have Wanted Me To Stick With You"

Remus and Harry.

In the seventh book, Harry Potter And The Deathly Hallows, Lupin's deepest fears come to the fore when Tonks falls pregnant with his child. Struck by horror at the prospect of his offspring inheriting his condition, Lupin finds an excuse to escape. He asks Harry, Ron, and Hermione if he can join them on their journey, advising Harry that it's what James would have wanted. Harry disagrees and argues with Lupin over his selfish and cowardly actions. This is the last major lesson that Lupin needs to learn; a moment that signifies a shift in his behavior. By the end of his life, Lupin is the person he was always meant to be, and the person his wife and child deserved.

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