The 29-year-old from Wellington got to sing with his coach and fellow builder Sir Tom Jones during the final of the ITV show on Saturday.
After singing Avril Lavigne’s Breakaway as his first song, Callum took to the stage with Sir Tom for a powerful rendition of Leonard Cohen’s Bird on the Wire, their voices reaching a crescendo in perfect harmony.
Sir Tom was visibly emotional, as was Callum, when he praised his singer saying: “He is a lovely fella and there weren’t too many lovely fellas around when I worked on building sites. He means it when he sings – I get honesty from him.”
The singer himself thanked Sir Tom for believing in him.
“I have doubted myself my whole life. Thanks to putting your faith in me and trusting me I finally believe in myself. I have always had a down on myself but now I know I need to be nicer to me. I am just having the time of my life and I hope I have made you proud.”
Sir Tom said: “I know you love doing the building but I know you want that big break. You have a heart of gold and a genuine kindness and when you sing you have that power.”
Callum was pipped to the top spot by duo Jen and Liv, will.i.am’s finalists, whose rap version of I’m Every Woman was a huge highlight of the show.
On social media Callum said it will be something he carries for the rest of his life.
Callum said: “I feel like a champion.
“To have had the time and experience from Sir Tom is priceless and something i will carry for the rest of my life.
“This is just the start for me. 2024 who knows what may bring.”
He added that the journey has been life changing and meeting some of the best people with the most incredible talent.
“The final episode was one to remember. Every single contestant throughout the entire show gave everything.”
He added that it was an honour to stand on stage with all the other contestants.
Not at any point did I ever feel competitiveness, it was all just love and support,” he said.
Watch Callum’s Bird on the Wire duet with Sir Tom Jones