Michael Gambon's Harry Potter Costars Honor Dumbledore Actor After His Death: He Was 'Magnificent'

Michael Gambon's Harry Potter costars are raising their wands to the late actor.

After news of Gambon's death at age 82 on Thursday, James Phelps and Jason Isaacs paid tribute to the star, who played Dumbledore in the Harry Potter films beginning with 2004's Harry Potter and the Prisoner of Azkaban.

"Magnificent Michael Gambon has died," Isaacs, 60, wrote on X (formerly known as Twitter). "I learned what acting could be from Michael in The Singing Detective — complex, vulnerable and utterly human."

"The greatest thrill of being in the Potter films was that he knew my name and shared his fearless, filthy sense of fun with me," added the actor, who appeared as the villainous Lucius Malfoy in the majority of the Harry Potter films.

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James, who played Fred Weasley in the movies, shared a touching story about Gambon from the set of 2009's Harry Potter and the Half-Blood Prince, where they "spent many hours" together.

"He was always very funny and very welcoming to share any knowledge he had," tweeted the actor, 37, whose twin brother Oliver Phelps played Fred's twin brother, George Weasley.

James went on to recall the "intense" clock-tower scene near the end of the movie. But between setups, Gambon helped the Phelps twins with their preparations for another project they were working on: a reading of Peter and the Wolf with the Manchester Hallé orchestra, which was something Gambon was familiar with.

"So we spent what should have been his downtime going over my weekend gig," James wrote. "It is a memory I've always had as one of the highlights of my HP days."

Fiona Shaw, who played Petunia Dursley in the series, told BBC Radio 4 that he was “a brilliant, magnificent trickster” who “varied his career remarkably and never judged what he was doing, he just played," according to The Guardian.

Bonnie Wright, who played Ginny Weasley in the eight Potter films, shared an image of Gambon as Dumbledore in 2004's Prisoner of Azkaban on Instagram and wrote that she "was forever in awe of Michael’s presence and performance."

"His deep mischievous voice between scenes would vibrate through the Great Hall," Wright, 32, shared. "He was Dumbledore through and through a constant, warm and guiding figure. Rest in peace Michael. Sending love to your family ❤️"

Gambon took over the part of Hogwarts headmaster Albus Dumbledore after the death of Richard Harris in October 2002. Harris played Dumbledore in the series' first two films. Richard's son, actor Jared Harris, tweeted on Thursday of Gambon: "Hilarious! A brilliant actor. I saw him on stage several times, and he lives unforgettably in my memory. He took over Dumbledore from my father, which was fitting as he over took Brando as my father’s favourite actor."

In addition to a celebrated career in theater and on television, Gambon had memorable roles in movies like Toys (1992), Sleepy Hollow (1999), Gosford Park (2001) and 2010's The King's Speech, in which he played King George V and was among the cast that won the SAG Award for outstanding performance by a cast in a motion picture. He was also nominated for two Emmy Awards and won four BAFTA Awards.

In 2012, Gambon received the Richard Harris Award from the British Independent Film Awards, an honor that acknowledges an actor who has contributed significantly to British film. In 1998, he received a knighthood from Queen Elizabeth.

Gambon died "peacefully" in the hospital, his representative confirmed in a statement to PEOPLE on Thursday, issued on behalf of his wife Lady Gambon and son Fergus.

“We are devastated to announce the loss of Sir Michael Gambon," the statement shared on Thursday began. "Beloved husband and father, Michael died peacefully in hospital with his wife Anne and son Fergus at his bedside, following a bout of pneumonia. Michael was 82."

"We ask that you respect our privacy at this painful time and thank you for your messages of support and love," the statement concluded.