A lot of things that have been said on "The Comedy Central Roast of Justin Bieber" cut close to the edge, and the jokes made at the Canadian singer's expense were sometimes mean, crass, and below the belt.

But Bieber, 21 took it all under stride, and even stressed during his speech how sorry he was for his bad behaviour and expressed gratitude to God for His grace and unconditional love.

"There was really no preparing me for this life. I was thrown into this at 12-years-old and I didn't really know what I was getting myself into," Bieber said. "There's been moments I'm really proud of, and a lot of moments I look back and I'm pretty disappointed in myself for. But the things that I've done really don't define who I am."

Bieber said that he is really looking forward to turning his life around and becoming the kind of person that people can actually look up to and be proud of. A friend of his told the singer before that how a person rises from a fall will ultimately define him as a man, and he is eager to show the world what kind of man he truly is.

"I'm excited for that challenge and I want to say thank you so much for taking this journey with me and I'm excited for you to see what's next. Thank you, God, for your grace and for never giving up on me," he said.

Bieber appeared on the cover of Men's Health magazine earlier this month and he revealed plans to change his life for the better, and that he wants to hold on to the "sense of purity" he had when he first started out in the music business.

"There's a part of me that I don't ever want to grow up," he admitted. "I want to always remain... to have that sense of purity inside of me where I don't... I don't want to lose that sense of purity."