When Harry arrived at Hogwarts, he started his magical education and was guided by some of the most talented people in magical society. Even though Harry didn't like some of them, like Sybill Trelawney and Severus Snape, there's no doubt that each of them contributed to his development, even Gilderoy Lockhart.
The Harry Potter series contains some of the most iconic quotes from books and movies, and some of them come from Harry's teachers. Fans are well acquainted with Albus Dumbledore's wise remarks or Minerva McGonagall's sarcastic comments, and some of these moments will forever live in their minds.
Madame Hooch
"You Leave Those Brooms Where They Are Or You’ll Be Out Of Hogwarts Before You Can Say ‘Quidditch.’"
When all the first-year students took their first flying classes, Neville had an accident and broke his wrist, for which Madame Hooch had to take him to the hospital wing. Before leaving, she threatened her students with suspension if they so much as touched their brooms.
Madame Hooch doesn't tolerate a lack of discipline in her class from her students and who knows what the repercussions would have been if she had spotted Harry using his broom instead of McGonagall. However, it's certainly likely that she would have seen her threat through to show that she isn't a teacher to be trifled with.
Horace Slughorn
"Taking Up A Post At Hogwarts Just Now Would Be Tantamount To Declaring My Public Allegiance To The Order Of The Phoenix! And While I'm Sure They're Very Admirable And Brave And All The Rest Of It, I Don't Personally Fancy The Mortality Rate."
After Dolores Umbridge is fortunately removed from her position as the Defense Against The Dark Arts teacher, Dumbledore gives her position to Severus Snape. In turn, he needs to find another Potions teacher, with his first option being Horace Slughorn, who had worked at Hogwarts several years ago.
However, Slughorn is not so happy about the idea. The world had just found out that Lord Voldemort was back, and associating with Dumbledore was a clear sign of defiance against You-Know-Who. Horace Slughorn was an excellent potions teacher, but he was definitely not a hero.
Sybill Trelawney
"The One With The Power To Vanquish The Dark Lord Approaches... Born To Those Who Have Thrice Defied Mim, Born As The Seventh Month Dies... And The Dark Lord Will Mark Him As His Equal, But He Will Have Power The Dark Lord Knows Not... And Either Must Die At The Hand Of The Other For Neither Can Live While The Other Survives."
Sybill Trelawney is known for her tendency for her dramatics and constantly incorrectly predicting her student's future - particularly Harry's death. Even though she has loyal followers, such as Parvati and Lavender, Professor Trelawney is more wrong than right, most of the time.
However, there have been two times she's acted as a medium for real prophecies, and the first time she, fortunately, did it in front of Albus Dumbledore. Funny enough, the divinations teacher doesn't have any recollection of these events.
Pomona Sprout
“Tentacula. Devil’s Snare. And Snargaluff Pods…Yes, I’d Like To See The Death Eaters Fighting Those.”
When everyone is getting ready to fight the Death Eaters in The Battle of Hogwarts, Pomona is one of the first ones to assume her battle stance. She immediately starts planning which of her plants are going to be the most useful against the Death Eaters, and it turns out there's more than one deadly option.
The world of Harry Potter offers a wide variety of magical plants, and most of them are very useful. Without the mandrakes, for example, wizards couldn't make the potion that cures petrification. For this reason, Herbology is one of the most important subjects at Hogwarts and it's taught by brilliant professor Pomona Sprout.
Filius Flitwick
"Saying The Magic Words Properly Is Very Important, Too -- Never Forget Wizard Baruffio, Who Said 'S' Instead Of 'Of' And Found Himself On The Floor With A Buffalo On His Chest."
When Professor Flitwick is teaching the first-year students how to perform the Wingardium Leviosa charm, he makes a strong emphasis on the importance of correct pronunciation and enunciation, which has to be clean and accurate to avoid accidents.
Using precise words is always important, but in the magical world, it can be the difference between life and death. If Hermione hadn't shown Ron the proper way to pronounce the spell, he couldn't have saved them from the troll in the girl's bathroom. Arguably, this is why many would declare Flitwick the best professor at Hogwarts.
Remus Lupin
“You Are Not Weak, Harry. The Dementors Affect You Worst Of All Because You Have True Horrors In Your Past. You Have Nothing To Be Ashamed Of."
When Harry faints in a Quidditch match due to the Dementors that were assigned to look for Sirius Black in Hogwarts, he doesn't understand how come he's the only student affected that much by these creatures. He brings his concern to Professor Lupin, who wisely explains to Harry the reason.
This is one of Remus Lupin's best quotes because he helps Harry to understand that he's stronger than he thinks. Even though it may seem that Harry is weaker than everyone else, the fact that he's gone through such horrible things in his life and he's still fighting for what he believes is right makes him all the stronger.
Rubeus Hagrid
"You're A Wizard, Harry."
After Harry spent all of his childhood with his muggles relatives, Hagrid is the one who delivers the news to Harry that he's a wizard. Since the Boy Who Lived had spent most of his life thinking he was an ordinary boy, this news completely changed Harry's life.
The role of Hagrid in Harry's life can't be underestimated. The giant is one of the most important people in the hero's journey. He became his first friend at Hogwarts and one of his most loyal allies. Even though Hagrid sometimes brings trouble - Norbert, for example - there's no doubt he always has the best intentions at heart.
Severus Snape
"Always."
When Harry sees Snape's memories, he finds out that his potions professor had been in love with his mother for most of his life. In one memory, Snape shows Dumbledore his Patronus, which was the same as Lily's, and the Headmasters asks him, "after all this time?" to which Snape replies, "always."
Snape spent most of his life trying to protect Lily Potter's son, not only because he was in love with her, but also because he was the one to blame for her murder. The fans loved Snape's redemption arc so much that this became one of Snape's most iconic quotes.
Minerva McGonagall
"I Wonder How You Expect To Gain An Idea Of My Usual Teaching Methods If You Continue To Interrupt Me? You See, I Do Not Generally Permit People Talking When I Am Talking."
When Dolores Umbridge becomes Hogwarts High Inquisitor, she starts to evaluate all Hogwarts professor's classes to assess if they were to the Ministry of Magic standards. Umbridge kept interrupting McGonagall's class, expecting the professor to acknowledge her.
However, Professor McGonagall understandably disliked Umbridge since she was making terrible changes in the school. Sadly, this quote by McGonagall didn't make the movies because everyone would have loved to see it.
Albus Dumbledore
"Happiness Can Be Found, Even In The Darkest Of Times, If One Only Remembers To Turn On The Light."
In the third Harry Potter movie, when Dumbledore receives the students at Hogwarts for the school year, he warns them about the Dementors that have been stationed in school grounds. Since these dark creatures that feed on a person's worse memories, Dumbledore's remind them to hold on to the light.
This is one of Dumbledore's best pieces of advice, not only because the Patronus Charm, the spell that wizards can use to scare a Dementor away, is literally pure light, but also because when people face dark times in their lives, is always good to remember to focus on the good things. Harry's victory and the end of the series depends mostly on Harry remembering to hold on to the people he loves.