The touching venue for funeral of private schoolboy and top judge's grandson who was swept to his death during Schoolies week

Teary students joined friends and family to fill the theatre at one of Australia's most elite schools for the funeral of teenager who died on his Schoolies trip.

Astin Gerstl, 18, was swept out to sea after becoming caught in a rip at Little Bay Beach on the NSW Mid North Coast at about 4.20pm on November 30.

With his HSC exams completed, he was celebrating the end of a chapter alongside several friends on the trip, but tragically did not get to experience the next.

Astin's funeral was held in the theatre of his former school, The King's School in Parramatta - western Sydney, on Monday.

He was a boarder at the school and is the grandson of former Supreme Court Justice Roddy Meagher, who died in 2011.

His family had requested the funeral be held in the theatre as Astin was a passionate actor who had performed many times on the stage.

Astin's father, Mark Gerstl, was the first to speak and said his son's family and friend's were 'shattered beyond words'.

'His life of nearly 18 years was cruelly and suddenly cut short,' he said.

Astin Gerstl (pictured) was swept out to sea on November 30

Astin Gerstl (pictured) was swept out to sea on November 30

Astin's father, Mark Gerstl (pictured), was the first speaker at the funeral on Monday

Astin's father, Mark Gerstl (pictured), was the first speaker at the funeral on Monday

The teenager's funeral was held in his school's theatre (pictured)

The teenager's funeral was held in his school's theatre (pictured)

Mr Gerstl extended a thank-you to those who helped in the search.

'He was never given warning and mother nature showed no mercy,' he said.

'...If I could swap places with Aston right now, I wouldn't hesitate.

'I don't know if I'll ever get over the fact that I wasn't where he needed me to be the most, to try and save him.'

Astin's body was found by a member of the public on December 5 at the same beach where he'd gone missing.

A massive crew spent hours looking for him but hazardous conditions forced searchers to suspend the operation.

Astin's mother, Amy Gerstl, thanked her son's friends who were with him when he disappeared. 

'The boys that were there with him at the time were treasured friends to him, and he was just so excited to be celebrating the end of school with them,' Mrs Gerstl said.

Astin (pictured) was a passionate actor and performed in several Red Cross concerts
Astin (pictured) had recently finished his HSC exams at The King's School in Parramatta

Astin (pictured) was a talented actor who had recently finished his HSC exams at The King's School in Parramatta

'I want to make a point of acknowledging the trauma that those boys must have gone through in the circumstances, particularly those that witnessed it directly.

'I'm so thankful he was with such a caring group of boys who did everything they could and were so on the ball and seeking help.'

Astin leaves behind two siblings, his little sister Alula and older brother Orion.

Before studying at King's, Astin attended its primary school counterpart, Tudor House in Moss Vale.

He was academically gifted and was set to continue his education at Sydney University, studying finance and economics.

However, his biggest passion was performing. 

'He loved being on stage, public speaking, piano, poetry recitals, getting awards, and of course he loved his drama performances,' Mr Gerstl said.

'He also performed in several comedies alongside his brother Orion in the Red Cross concerts.

Emergency crews were called to Little Bay Beach when Aston didn't emerge from the water

Emergency crews were called to Little Bay Beach when Aston didn't emerge from the water 

Astin's body was found by a member of the public on December 5 following an extensive search

Astin's body was found by a member of the public on December 5 following an extensive search

'...I'll never forget his year 11 solo drama performance. He went through a full range of emotions including laughing, anger and crying. It moved me so much.

'All his work culminated in the prestigious onstage nomination for the HSC in both his group and solo performances.

'There would be no-one more proud of this than Astin himself.'

Mrs and Mr Gerstl said they hoped their son would be widely remembered for much more than how his life ended.

'It's now been 50 days since Astin was taken. He was too good for this world,' Mr Gerstl said.

'I only realised since his passing and writing these words that the name Astin is an anagram of saint.

'Astin, our saint, I love you beyond words.'