Hailey Bieber opened up about her faith and marriage to pop star Justin Bieber in an intimate sit-down interview with the Hillsong Channel on YouTube.

Asked what she had learnt from being married, Hailey - a model and the daughter of Christian actor Stephen Baldwin - said it was important to compromise and let go of her single life. 

"If you don't want to compromise, don't get married," she said.

"If you're not willing to step into a new life with someone - and you have to kind of say goodbye to some things from your past, and say goodbye to some old conveniences and luxuries and friends and people and time and space and energy - don't get married."

The Hillsong regular said that marriage had forced her to grow up and grow out of some things. 

"You can't have the best of both worlds," she continued. 

"You can't still be living your single life and be married....I stepped out of my life as a single woman and stepped into my life as a married woman and that's a whole new world in comparison to what it was before - and I would not change anything."

She admitted marrying Justin had come with some challenges on a personal level, especially the pressure of being compared to other women and the criticism the pair faced for being together and getting married. 

But she said Justin had helped her through those challenges by affirming her and pointing her back to her faith.

"He is constantly reminding me, like, who does Jesus say you are? What does the Bible say? What are we like? Where are we finding our truth?" she said. 

Recalling her star-studded wedding in South Carolina last September, she said it had been the best day of her life in spite of a few mishaps, like one of the chapel pews breaking in the middle of her ceremony.

Asked about her favourite moment from the day, she said that taking communion together with Justin in front of their guests had been "really powerful and significant".

In the wideranging interview, Hailey opened up about some of her struggles with feelings of guilt and shame in the first "six or seven months" of her marriage, some of which she said were the result of her Christian upbringing. 

"I carried a lot of guilt," she said. 

"I think where it stems from for me is that I was raised in a Christian household. I grew up with Christian parents, and I just think I put extra guilt on myself to be this, like, good girl and fill this role of being this goody two shoes good girl. 

"And I just think what I learned leading up to being married is that it's just not realistic." 

She said, though, that she had learnt that guilt, shame and past regrets do not need to define a person, and that her faith in Christ is molding her into a better person.

"We're constantly evolving, especially in Jesus," she said.

"Like, our relationship with Christ is always going deeper and deeper and deeper and where I was before I was a wife and who I was before I was a wife is not who I am now."