Raised a Christian, he now claims to not be religious, according to the Daily Mail.
The Canadian pop star posted: "Vindicate me, my God, and plead my cause against an unfaithful nation. Rescue me from those who are deceitful and wicked - Psalms 43."
He added a photo of himself reading a book and wrote: "I'm not religious nor do I think I have ANYTHING figured out. That's why I call out on God to help me through what I can't do on my own."
Justin Bieber has often spoken about his faith and last year asked for forgiveness from Jesus and God in a Christian rap video.
"Developing my relationship with God has been the coolest thing I've experienced, to know that I'm not alone and I don't have to live in fear," he also said in the post.
