Bieber, 24, and Christian model Hailey Baldwin, 21, who have been in relationship for around one month, became engaged in the Bahamas on Saturday night.
Baldwin's father - Christian actor Stephen Baldwin - appeared to confirm the news in a tweet, before swiftly deleting it.
In the now-deleted tweet, Stephen wrote: "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."
He also tagged Bieber's parents Jeremy Bieber and Pattie Mallette and wrote "Congrats", while sharing Ephesians 5:25-26: "Husbands, love your wives, just as Christ loved the church and gave himself up for her, to make her holy, cleansing her by the washing with water through the word."
Hailey Baldwin, who attends Hillsong Church with Bieber, has been vocal about her Christian faith.
In an interview with Teen Vogue in 2016 she shared that she was raised in church and thinks it's important for everyone to have a personal relationship with God.
She added: "I think that God kind of put me in the place in my life to not be quiet about it, not be quiet about him, but to reach people and to inspire people.
"It's a big part of my life. A lot of my closest friends, people that I trust the most, people that have been there for me the most are all people that are in my church and people that are kind of trying to guide me from the outside perspective."
According to American gossip site TMZ, two eyewitnesses claim to have seen Bieber ask for Baldwin's hand in marriage at a restaurant at a resort in the Bahamas.
Bieber's security team is believed to have told others at the restaurant to put their phones away before he popped the question in front of everybody there.
American entertainment site People quoted a source close to the couple as saying: "It's kind of a surprise, but kind of not.
"Justin has been extremely happy these past few weeks. He has known Hailey for a long time. This might seem sudden, but they know each other very well."
Bieber's father Jeremy also hinted at the engagement with a cryptic post on Instagram.
He shared a photo of the 'Sorry' singer against a sunset and wrote: "@justinbieber Proud is an understatement! Excited for the next chapter!"
Bieber is said to have previously dated Baldwin in between seeing pop star Selena Gomez.
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