Justin Bieber has been baptised in a bathtub in New York.

The 20-year-old pop star, who has apologised for making racist remarks in two videos which emerged this month, attempted to wash away his sins with a baptism carried out in a bathroom.

Pastor Carl Lentz, who works with Justin in America, told TMZ he spent a week doing intense Bible study with the star last month before the videos went public, after he claims he was approached by a man asking for a $1 million payout to keep them private.

Justin had been studying Bible passages and attending services but couldn't find a church where he could be baptised without being interrupted, so he chose to do it in a friend's bathroom to keep it private.

Meanwhile, Justin has received support from a number of black entertainers, including Usher, Whoopi Goldberg, Mike Tyson, Young Money, floyd mayweather and Souljah Boy, who claim he is not racist and was just a naive 14-year-old boy when he used the N-word and sang a song about joining the Ku Klux Klan.

Usher, who has been his mentor and manager throughout his career, wrote on Instagram: ''As I have watched Justin Bieber navigate difficult waters as a young man, I can tell you that he hasn't always chosen the path of his greatest potential, but he is unequivocally not a racist.

''What he was five years ago was a naive child who did not understand the negative power and degradation that comes from playing with racial slurs. What he is now is a young man faced with an opportunity to become his best self, an example to the millions of kids that follow him to not make the same mistakes.''