Justin Bieber reading Christian marriage book as he prepares to wed Hailey Baldwin

Justin Bieber with Tim Keller's 'The Meaning of Marriage'(Screengrab/TMZ)

A Baptist pastor has hailed Justin Bieber for reading and promoting Christian author Tim Keller's book on marriage following his engagement to model Hailey Baldwin.

TMZ released a video of the popstar leaving Baldwin's apartment in New York City on Wednesday night, where he briefly stopped to chat with fans before going into a car. Bieber was holding Keller's 2011 book The Meaning of Marriage, and even showed it to the camera, saying: "You have good days and you have bad days. It's not real if it doesn't have any bad days."

Murray Campbell, lead pastor at Mentone Baptist Church in Melbourne, explained in The Gospel Coalition on Friday about why the book, and the world-famous Christian pop star's promotion of it, is important.

Campbell said that some in the media find the book controversial for its defence of monogamy and for telling men and women to abstain from sex before marriage, as well as for suggesting that wives should submit to their husbands.

"Yes, all of these things are unpopular today, but none of them are controversial in most contexts," Campbell wrote.

"They are, and have been, shared by Christians (and many others) all over the world for millennia. These are aspects of a marriage that are taught and encouraged in the Bible. However what the Kellers achieve (following the Bible) is to frame marriage relationships in a consistent and attractive way that helps makes sense of why marriage should be monogamous and why there are gender complementary roles in a marriage."

The pastor, who says that he uses Keller's book regularly for both pre-marriage and marriage counselling at his church, warned that too often people "parody and caricature ideas that we don't like or can't comprehend, rather than taking the harder and more honest approach, which is to understand concepts on their own terms."

"In reading the book, we discover that the Kellers are only too aware of how marriage is being reframed in Western cultures, and while critiquing these trends, they are not sending readers back to the conservative 1950s either," he added.

"That's why it's worth reading the book; it will surprise. Tim and Kathy Keller are neither mirroring the less-than satisfying views of sex and relationships that turn up on Netflix and Amazon, neither are they reproducing unhelpful marital myths from previous generations."

Campbell admitted that he is "milking these Justin Bieber photos" in order to promote a book that he really likes, because he believes The Meaning of Marriage "is a great book for marriage."

"It certainly seems as though this young engaged couple also believe it's worth reading," he added, referring to Bieber and Baldwin.

The couple's engagement was revealed back in July, though the pair have not opened up to the media about the details.

Stephen Baldwin, an actor and devout born-again Christian, who is the model's father, posted on Twitter a congratulatory tweet at the time, which has since been removed.

"Sweet smile on my face ! me&wife (Kennya) Always pray 4 Gods will !! He is moving in the hearts of JB&HB Let's all pray for His will to be done...Love you 2 so much !!! #Godstiming #bestisyettocome Congrats ❤ @JeremyBieber @pattiemallette #PraiseJesus," read the actor's tweet.

This article was originally published in The Christian Post and is re-published here with permission