Justin Bieber has reportedly ditched alcohol and drugs so he can put his bad boy behaviour behind him and relaunch his pop career.

The Baby hitmaker issued a public apology to his fans this week (begs26Jan15) for being "arrogant" and "conceited" in recent years and for letting his wild antics get in the way of his music career.

He insisted he was "pretending" being a bad boy, and in a further bid to clean up his act, Bieber has reportedly quit drink and drugs thanks to his close friendship with Christian pastor Carl Lentz.

A source tells Britain's The Sun newspaper, "There's no one Justin looks up to more than Carl. He's had a huge influence on him... They spoke at length about how he can get his life and career back on track and both agreed that getting rid of alcohol and drugs was the natural first step.

"Justin has made promises like this before but this time we all genuinely believe he is clean... His manager Scooter Braun was very clear that, until Justin sorted himself out, his music comeback was on hold."

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